153 Sentences With "acicular" | Random Sentence Generator

They describe contaminants in talc from J&J's Italian supplier as fibrous and "acicular," or needle-like, tremolite.

In a pair of reports from 1957 and 1958, the lab said the talc contained "from less than 1 percent to about 3 percent of contaminants," described as mostly fibrous and "acicular" tremolite.

Natrolite showing acicular crystal habit __NOTOC__ Acicular, in mineralogy, refers to a crystal habit composed of slender, needle-like crystals. Crystals with this habit tend to be fragile. Complete, undamaged acicular specimens are uncommon. The term "acicular" derives from the Late Latin "acicula" meaning "little needle".

Acicular crystals from the Wessels Mine in South Africa Bultfonteinite is transparent and pale pink to colorless. The mineral occurs as radiating prismatic acicular crystals and radial spherules up to .

Minerals with an acicular habit include mesolite, natrolite,Hamilton, W.R.

The crystals in the mammillary layer are acicular or wedge-like.

Selenite crystals that exhibit in either reticular or acicular habits, satin spar, in general (as fibrous crystals are thin and narrow), desert roses that are thinly bladed, and gypsum flowers, particularly acicular gypsum flowers, can be quite brittle and easily broken.

Usually of a white or light greenish color and vitreous lustre, in acicular crystallizations.

Chlorite and to a lesser extent actinolite typically exhibit small, flat or acicular crystal habits.

Wollastonite or calcium metasilicate is a naturally occurring industrial mineral that has an acicular structure.

Manganese – Cleans impurities in steels (most commonly used to tie up sulfur) and also forms oxides that are necessary for the nucleation of acicular ferrite. Acicular ferrite is desirable in HY-80 steels because it promotes excellent yield strength and toughness. Silicon – Oxide former that serves to clean and provide nucleation points for acicular ferrite. Chromium – Is a ferrite stabilizer and can combine with carbon to form chromium carbides for increased strength of the material.

In recent decades, barium ferrite has replaced acicular oxides; without any dopants, the acicular oxides produce very low coercivity values, making the material very magnetically soft, while barium ferrite's higher coercivity levels make the material magnetically hard and thus a superior choice for recording material applications.

Nitraniline forms yellow, acicular crystals, little soluble in cold water, but freely soluble in alcohol and ether.

Some minerals like creedite form prismatic crystals that appear to be acicular, but are instead prismatic in a bladelike form; these can be told apart by the fact that all prismatic crystals are less sharp, sometimes are tipped with a pyramidal shape, and keep a standard cross-section shape with straight edges. Acicular crystals differ from fibrous crystals in their thickness; crystals with a fibrous habit are much thinner, sometimes to the point of being flexible like hair, while acicular crystals are thicker and rigid.

In a more humid environment, fibrous crystals or acicular radial aggregates are formed. Both recrystallized and synthetic huemulite have tabular habit.

Acantholimon libanoticum is evergreen. The simple leaves are alternate. They are acicular with entire margins. It flowers from July to August.

Parapodia with elongate acicular lobes with both acicula penetrating epidermis; neuropodia with a supra-acicular process. Notochaetae stout with distinct rows of spines and blunt tip. Neurochaetae more numerous and more slender, with distinct rows of spines distally and exclusively unidentate tips. The genus was described in 1865, with a modern redescription in Barnich & Fiege (2010).

Sukow suggested that the coloration may be due to aggregates of acicular crystals of copper minerals scattered or concentrated throughout the datolite nodule.

Strictly speaking, the word refers to a growth habit that is slender and tapering to a point. Prismatic crystals are not acicular; however, colloquial usage has altered the commonly understood meaning of the word. When writing for mineralogical publications, authors should restrict their usage of "acicular" to crystals with the tapering growth habit. To add to the confusion, some minerals are described with various morphological terms.

Generally, HY-80 is welded with an AWS ER100S-1 welding wire. The ER100S-1 has a lower Carbon and Nickel content to assist in the dilutive effect during welding discussed previously. An important function of the filler metal is to nucleate acicular ferrite. Acicular ferrite is formed with the presence of oxides and the composition of the filler metal can increase the formation of these critical nucleation sites.

Kenhsuite is an extremely rare mineral, known in very few localities in the world. In the type locality, it was found as extremely small acicular or tabular crystals, less than 100 microns in size. The locality where the best specimens appear is the Oriental mine, in Chóvar, Castellón (Spain), where the acicular crystals usually exceed one millimeter, forming centimetric aggregates of fan-shaped crystals. In these two deposits it appears associated with corderoite and cinnabar.

The posterior parapodium has cushion-like cirri. The setae include winged capillaries and pseudocompound forms on the anterior parapodia and winged capillaries, comb-setae and acicular setae on the posterior ones.

It could mean that there is a hitherto uncharacterized kinetic isotope effect associated with the incorporation of sulfate into a particular carbonate texture (shrubs vs. nodules vs. acicular cements vs. other conformations).

Scientific Reports, 3, 2020 (2013). #R. D. Field and D.J. Thoma. "Crystallographic and Kinetic Origins of Acicular and Banded Microstructures in U-Nb Alloys". J. of Nuclear Materials, 436, 105-117 (2013). #A.

The individual crystals of anthodites develop in a form described as "acicular" (needle-like) and often branch out as they grow. They usually grow downward from a cave's ceiling. Aragonite crystals are contrasted with those made of calcite (another variety of calcium carbonate) in that the latter tend to be stubby or dog- tooth-like ("rhombohedral", rather than acicular). Anthodites often have a solid core of aragonite and may have huntite or hydromagnesite deposited near the ends of the branches.

Scolecite can therefore be distinguished from natrolite by an optical examination, since the acicular crystals do not extinguish parallel to their length between crossed nicol prisms. Twinning on the ortho-pinacoid is usually evident.

It is bright yellow in colour and usually has an acicular crystal habit. It has a Mohs hardness of 2–3.Pierrot R, Toussaint J, Verbeek T. Bull. Soc. Franc. Mineral. Crist. 1965; 88: 132.

Both selenite crystals and gypsum flowers sometimes form quite densely in acicular mats or nets; and can be quite brittle and fragile. Gypsum flowers are usually attached to a matrix (can be gypsum) or base rock.

White acicular crystals of wollastonite (field of view 8 mm) from the Central Bohemia Region, Czech Republic The acicular nature of many wollastonite products allows it to compete with other acicular materials, such as ceramic fiber, glass fiber, steel fiber, and several organic fibers, such as aramid, polyethylene, polypropylene, and polytetrafluoroethylene in products where improvements in dimensional stability, flexural modulus, and heat deflection are sought. Wollastonite also competes with several nonfibrous minerals or rocks, such as kaolin, mica, and talc, which are added to plastics to increase flexural strength, and such minerals as barite, calcium carbonate, gypsum, and talc, which impart dimensional stability to plastics. In ceramics, wollastonite competes with carbonates, feldspar, lime, and silica as a source of calcium and silicon. Its use in ceramics depends on the formulation of the ceramic body and the firing method.

Strontianite occurs in several different habits. Crystals are short prismatic parallel to the c axis and often acicular. Calcium-rich varieties often show steep pyramidal forms. Crystals may be pseudo hexagonal due to equal development of different forms.

In E. stramineus, the areoles are circular in shape and normally 7–15 mm apart. Each areole contains average 2–4 central spines and 7–10 radial spines in which radial spines are acicular and 2–3 cm in length.

The length of the shell attains 3.85 mm, its diameter 1.25 mm. (Original description by Hedley) The minute shell is acicular and thin. Its colour is amber-brown, passing to purple on the apex. It contains five whorls, wound obliquely.

Millerite is a nickel sulfide mineral, NiS. It is brassy in colour and has an acicular habit, often forming radiating masses and furry aggregates. It can be distinguished from pentlandite by crystal habit, its duller colour, and general lack of association with pyrite or pyrrhotite.

Luxullianite from Cornwall, showing dark patches of tourmaline and pink crystals of orthoclase Thin section of luxullianite from Cornwall, showing clusters of radially-arranged, acicular, greenish tourmaline crystals Luxullianite (also Luxulyanite, Luxulianite) is a rare type of granite, notable for the presence of clusters of radially-arranged acicular tourmaline crystals enclosed by phenocrysts of orthoclase and quartz in a matrix of quartz, tourmaline, alkali feldspar, brown mica, and cassiterite. The name originates from the village of Luxulyan in Cornwall, England, where this type of granite is found. An example may be seen in the Duke of Wellington's monument at St Paul's Cathedral in London.

The length of the shell attains 5.5 mm, its diameter 2 mm. (Original description) The small, acuminate shell is excavate at the base and below the suture. Its colour is buff, sometimes suffused with chocolate. An acicular protoconch of three whorls is followed by five adult whorls.

Xonotlite is a mineral with the chemical formula Ca6Si6O17(OH)2. It crystallizes in the monoclinic - prismatic crystal system with typically an acicular crystal form or habit. It can be colorless, gray, light gray, lemon white, or pink. It is transparent with a vitreous to silky luster.

Muscovite is clear and sillimanite is the more acicular- fibrous mineral within the dark zone of the image. In cross polarized light (Fig. 3b) muscovite displays colorful birefringence and sillimanite is of the variety "fibrolite". Sillimanite is considered a diagnostic mineral for peraluminous S-type granites.

In groups of acicular crystals it is frequently seen penetrating quartz as in the fléches d'amour from Graubünden, Switzerland. In 2005 the Republic of Sierra Leone in West Africa had a production capacity of 23% of the world's annual rutile supply, which rose to approximately 30% in 2008.

Bayleyite is a uranium carbonate mineral with the chemical formula: Mg2(UO2)(CO3)3·18(H2O). It is a secondary mineral which contains magnesium, uranium and carbon. It is a bright yellow color. Its crystal habit is acicular but is more commonly found as crusts on uranium bearing ores.

Lanarkite is a mineral, a form of lead sulfate with formula Pb2(SO4)O. It was originally found at Leadhills in the Scottish county of Lanarkshire, hence the name. It forms white or light green, acicular monoclinic prismatic crystals, usually microscopic in size. It is an oxidation product of galena.

Wollastonite has an acicular structure with a relatively high specific gravity and high hardness. This filler can improve moisture content, wear resistance, thermal stability, and high dielectric strength. Wollastonite competes with platy filler substances like mica and talc and also can be used to replace glass fibers when creating thermoplastics and thermosets.

Natrolite is a mineral series in the zeolite group; this sample has a very prominent acicular crystal habit. Tectosilicates, also known as framework silicates, have the highest degree of polymerization. With all corners of a tetrahedra shared, the silicon:oxygen ratio becomes 1:2. Examples are quartz, the feldspars, feldspathoids, and the zeolites.

Getchellite turns darker red when heated, becoming black by the time it reaches its melting point. Close to this temperature it sublimes (changes directly from a solid to a vapor) and recrystallizes on cooler surfaces as minute acicular black crystals. Melting point: 340 °C to 355 °C. Boiling point: near 470 °C.

Clinoclase is a hydrous copper arsenate mineral, Cu3AsO4(OH)3. Clinoclase is a rare secondary copper mineral and forms acicular crystals in the fractured weathered zone above copper sulfide deposits. It occurs in vitreous, translucent dark blue to dark greenish blue colored crystals and botryoidal masses. The crystal system is monoclinic 2/m.

Creedite is a calcium aluminium sulfate fluoro hydroxide mineral with formula: Ca3Al2SO4(F,OH)10·2(H2O). Creedite forms colorless to white to purple monoclinic prismatic crystals. It often occurs as acicular radiating sprays of fine prisms. It is translucent to transparent with indices of refraction of nα = 1.461 nβ = 1.478 nγ = 1.485.

Parapodia with elongate acicular lobes are present, with both acicula penetrating the epidermis in notopodium but not neuropodium. The notochaetae are stout, with few rows of spines and slightly notched tip. The neurochaetae are more slender and more numerous, have faint rows of spines distally, and feature minutely bidentate or simple (unidentate) tips.

Besides the storage polysaccharide inulin (C6H12O6[C6H10O5]n), a polymer of fructose, the root contains helenin (C15H20O2), a stearoptene, which may be prepared in white acicular crystals, insoluble in water, but freely soluble in alcohol. When freed from the accompanying inula-camphor by repeated crystallization from alcohol, helenin melts at 110 °C.

Cuprosklodowskite is a secondary uranium mineral formed by alteration of earlier uranium minerals. Its empirical formula is Cu(UO2)2(HSiO4)2·6(H2O). Cuprosklodowskite is a nesosilicate mineral, It is grass green to dark green in color, and its crystal habit is typically acicular, flat bladed crystals. It is a strongly radioactive mineral.

Body dorsoventrally flattened, short, with 26 segments and 12 pairs of elytra on segments 2, 4, 5, 7, 9, 11, 13, 15, 17, 19, 21, and 23. Prostomium with three antennae; lateral antennae continuous with prostomium, laterally to median antenna. Parapodia with elongate acicular lobes with both acicula penetrating epidermis. Notochaetae slender and densely serrated.

The diffuse and multi-branched shrub typically grows to a height of . The glabrous branchlets have minute stipules and tend to be a red-brown colour at the extremities and age to a light-grey colour. The sessile acicular phyllodes have a length of and are around . It blooms from August and produces yellow flowers.

Ruizite from Arizona Ruizite is translucent and orange to red- brown in color with an apricot yellow streak. The mineral occurs as euhedral prisms up to or as radial clusters of acicular (needle-like) crystals. Ruizite is common at the Christmas mine. The mineral is known from Arizona, Pennsylvania, and Northern Cape Province, South Africa.

Mesolite is a tectosilicate mineral with formula Na2Ca2(Al2Si3O10)3·8H2O. It is a member of the zeolite group and is closely related to natrolite which it also resembles in appearance. Mesolite crystallizes in the orthorhombic system and typically forms fibrous, acicular prismatic crystals or masses. Radiating sprays of needlelike crystals are not uncommon.

Ulrichite is a rare green uranium phosphate mineral (CaCu(UO2)[PO4]2·4H2O).Mindat It crystallizes as monoclinic prisms which occur as apple green acicular radiating clusters. It is radioactive and exhibits strong yellow fluorescence under ultraviolet radiation. Ulrichite was first described in 1988 for samples from the Lake Boga granite quarry, Lake Boga, Victoria, Australia.

Acicular setae provide support. Locomotor chaetae are for crawling, and are the bristles that are visible on the exterior of the Polychaeta. They are cylindrical in shape, found not only in sandy areas, and they are adapted to burrow. They often cling to seagrass (posidonia) or other grass on rocks and sometimes gather in large groups.

Elytra 15 pairs, 36–40 segments. Lateral antennae inserted ventrally (beneath prostomium and median antenna). Neuropodia deeply incised vertically, so that the neurochaetae emerge from a prominent division between the pre-chaetal (=acicular) lobe and the post-chaetal lobe. Notochaetae present, hooked neurochaetae in anterior-most segments, bidentate neurochaetae absent (summarised from detailed diagnosis of Ravara & Cunha, 2016).

Bacidia is a lichenized genus of fungi in the family Ramalinaceae. The genus was first described by Giuseppe De Notaris in 1846. Species in the genus are crust-like lichens with stemless apothecia; they have green algae (chloroccoid) as photobionts. Their asci have 8 colorless, cylindrical to acicular, multiseptate spores, with curved and thread-like conidia.

It crystallizes in the monoclinic-prismatic crystal system. It occurs as transparent to translucent orange-brown aggregates of subparallel acicular crystals up to 10 mm in length, and as patches of yellow, fibrous crystals. It has a white to very pale yellow streak and vitreous luster. It is brittle, with distinct {100} and {001} cleavages, and a conchoidal fracture.

Time-temperature transformation (TTT) diagram. The red line shows the cooling curve for austempering. Austempering is heat treatment that is applied to ferrous metals, most notably steel and ductile iron. In steel it produces a bainite microstructure whereas in cast irons it produces a structure of acicular ferrite and high carbon, stabilized austenite known as ausferrite.

Epsomite is a hydrous magnesium sulfate mineral with formula MgSO4·7H2O. Epsomite crystallizes in the orthorhombic system as rarely found acicular or fibrous crystals, the normal form is as massive encrustations. It is colorless to white with tints of yellow, green and pink. The Mohs hardness is 2 to 2.5 and it has a low specific gravity of 1.67.

It is commonly found as radiating clusters of acicular needle-like crystals in cavities in sulfide rich limestone and dolomite or in geodes. It is also found in nickel-iron meteorites, such as CK carbonaceous chondrites. Millerite was discovered by Wilhelm Haidinger in 1845 in the coal mines of Wales. It was named for British mineralogist William Hallowes Miller.

Siderotil is an iron(II) sulfate hydrate mineral with formula: FeSO4·5H2O which forms by the dehydration of melanterite.Mindat.org Copper commonly occurs substituting for iron in the structure. It typically occurs as fibrous or powdery encrustations, but may also occur as acicular triclinic crystals. It was first described in 1891 for an occurrence in the Idrija Mine, Idrija, Slovenia.

Tellurite is a rare oxide mineral composed of tellurium dioxide (TeO2). It occurs as prismatic to acicular transparent yellow to white orthorhombic crystals. It occurs in the oxidation zone of mineral deposits in association with native tellurium, emmonsite and other tellurium minerals. Its name comes from Tellus, which is the Latin name for the planet Earth.

Cuspidine is a fluorine bearing calcium silicate mineral (sorosilicate) with formula: Ca4(Si2O7)(F,OH)2. Cuspidine crystallizes in the monoclinic crystal system and occurs as acicular to spear shaped pale red to light brown crystals. It is a member of the wöhlerite group. Cuspidine was first described in 1876 for an occurrence in Monte Somma, Italy.

In mass, the spores appear yellowish-brown, especially when they are dry. Viewed under the microscope, they appear hyaline (translucent). The spores are variable in size, but typically in the range of 30–95 by 1.5–2.5 µm. They may be non-or several septate, slender and pointed (acicular), and have an outer wall with a gelatinous layer.

Mottramite is an orthorhombic anhydrous vanadate hydroxide mineral, PbCu(VO4)(OH), at the copper end of the descloizite subgroup. It was formerly called cuprodescloizite or psittacinite (this mineral characterized in 1868 by Frederick Augustus Genth). Duhamelite is a calcium- and bismuth-bearing variety of mottramite, typically with acicular habit. Mottramite is a member of the adelite-descloizite group.

The upper central spine is white to tan and is curved and strongly flattened. Radial spines have length up to about and are white in color. There are about 6-8 radial spines per areole which are acicular. Seeds are black to light brown in color, and are 2.2-2.5 mm wide, with a rounded papillae.

In the Gulf coast of Louisiana and Texas, strontianite occurs with celestine in calcite cap rock of salt domes. At the Minerva Number 1 Mine (Ozark-Mahoning Number 1 Mine) Ozark-Mahoning Group, Cave-in-Rock, Illinois, in the Kentucky Fluorspar District, Hardin County strontanite occurs as white, brown or rarely pink tufts and bowties of acicular crystals with slightly curved terminations.Rocks & Minerals (2010) 85-3:212 In the Silurian Lockport Group, Central and Western New York strontianite is observed in cavities in eastern Lockport, where it occurs as small white radiating sprays of acicular crystals.Rocks & Minerals (2009) 84-4:332 In Schoharie County, New York, it occurs in geodes and veins with celestine and calcite in limestone, and in Mifflin County, Pennsylvania, it occurs with aragonite, again in limestone.

Cherry-red realgar crystals atop a matrix, and a sharp acicular spray of the rare species picropharmacolite (white needles) below Reedmergnerite, Dara-i-Pioz, Tajikistan Rhodizite crystal: Tetezantsio village, Ampasagona, Vakinankaratra region, Antananarivo Province, Madagascar Chalcopyrite, quartz, rhodochrosite (red) Octahedron Pocket, Mini King Raise, Sweet Home Mine, Alma, Colorado, US Rhodonite on galena. Broken Hill, Yancowinna County, New South Wales, Australia Rosasite. Ojuela Mine, Mapimí, Municipio de Mapimí, Durango, Mexico Roselite from Agoudal Centre Quarry, Ouarzazate Province, Souss-Massa-Draâ Region, Morocco Two crystals of translucent, cherry red ruby in matrix Rutherfordine from Musonoi Mine, Kolwezi, Western area, Katanga Copper Crescent, Katanga Golden acicular crystals of rutile radiating from a center of platy hematite Rutile. Itambacuri, Doce valley, Minas Gerais, Southeast Region, Brazil #Raadeite (allactite: IMA1996-034) 8.

The meteorite is a coarse octahedrite (mean bandwidth 1.34mm) with narrow cloudy taenite bands separating the kamacite lamellae. Occasional areas of coarse to fine acicular plessite and net plessite are Neumann lines and rhabdites. Sparsely developed Brezina lamellae and fine-grained globular schreibersite are present. At one exterior surface, a heat-affected zone 0.1mm thick containing unequilibrated alpha(sub)2-kamacite is preserved.

The length of the shell attains 10 mm, its diameter 3 mm. (Original description) The acicular shell is thin, but boldly sculptured, contracted at the suture, excavate at the base. The siphonal canal is produced and recurved. The colour of the shell is pale yellow, with two rufous brown zones, one above, the other below the periphery, both interrupted by the ribs.

Isabelia have unifoliated ovoid to fusiform pseudobulbs, linear or acicular leaves, and erect apical inflorescence bearing one of few flowers. The flowers have petals, sepals and labellum of the same color, which can be white, pale pink or magenta. Their sepals are widely elliptical to ovate; the petals can be narrower and oblong or wider elliptic. The labellum is entire and oblong.

Acicular crystals of rutile protruding from a quartz crystal In large enough quantities in beach sands, rutile forms an important constituent of heavy minerals and ore deposits. Miners extract and separate the valuable minerals – e.g., rutile, zircon, and ilmenite. The main uses for rutile are the manufacture of refractory ceramic, as a pigment, and for the production of titanium metal.

Aikinite is a sulfide mineral of lead, copper and bismuth with formula PbCuBiS3. It forms black to grey or reddish brown acicular orthorhombic crystals with a Mohs hardness of 2 to 2.5 and a specific gravity of 6.1 to 6.8. It was originally found in 1843 in the Beryozovskoye deposit, Ural Mountains. It is named after Arthur Aikin (1773–1854), an English geologist.

This perennial, densely tufted, hairy plant has a woody base and flowering stems up to in length. The stems are wiry and lignified, with acicular leaves with three veins, curving to the side to a greater of lesser extent. The flowers are grouped in glandular flower-heads, the individual flowers being white and five-petaled. The inflorescence is a 1–8-flowered cyme.

Mixite is a rare copper bismuth arsenate mineral with formula: BiCu6(AsO4)3(OH)6·3(H2O). It crystallizes in the hexagonal crystal system typically occurring as radiating acicular prisms and massive encrustations. The color varies from white to various shades of green and blue. It has a Mohs hardness of 3.5 to 4 and a specific gravity of 3.8.

There are about 12 radial spines, to long, that are acicular and terete. However, there are fewer central spines, only 4, that tend to be angled and elongated at around . One of the central spines is hooked at its apex as well. This cactus' flowers are large, usually to , and display a yellow color with an inner scarlet color in some forms.

Sklodowskite is a uranium mineral with the chemical formula: Mg(UO2)2(HSiO4)2·5H2O. It is a secondary mineral which contains magnesium and is a bright yellow colour, its crystal habit is acicular, but can form in other shapes. It has a Mohs hardness of about 2-3. It is named after the maiden name of Marie Skłodowska Curie.

Black acicular crystals of the rare Pb-Ag sulfide from a Colorado locality: Mike Mine, San Juan Co., Colorado, United States Berryite is a mineral with the formula Pb3(Ag,Cu)5Bi7S16. It occurs as gray to blue-gray monoclinic prisms. It is opaque and has a metallic luster. It has a Mohs hardness of 3.5 and a specific gravity of 6.7.

An illustration of the species It has numerous glochids or microspines, 3–12 mm long, acicular, slender, spreading, forming a dense cluster. They are normally golden yellow to dark red in color. It has often no spines, or rarely one to three, which are reflexed. They are of a yellowish or toasted colour with a brownish base, up to 3 cm in length.

H red:O green:B violet:Mn center of yellow tetrahedrons:P Seamanite is formed of acicular crystals elongated along [001] and showing the faces {110} and {111} up to one centimeter. It has an orthorhombic crystal system and the Pbnm space group. The parameters of its unit cell are: a=7.811 Å, b=15.114 Å, c=6.691 Å, Z=4 units per unit cell.

Hodgkinsonite is a rare zinc manganese silicate mineral Zn2MnSiO4(OH)2. It crystallizes in the monoclinic system and typically forms radiating to acicular prismatic crystals with variable color from pink, yellow-red to deep red. Hodgkinsonite was discovered in 1913 by H. H. Hodgkinson, for whom it is named in Franklin, New Jersey, and it is only found in that area.Mineral Galleries .

Its maxillae have seven pairs of free denticles. It counts with two peristomial segments without setae. It counts with a cirriform acicular lobe, its supraacicular chaetae being simple, while the subacicular chaetae are compound, and exhibit serrated blades. Its pygidium has a terminal anus, with two pygidial cirri that measure as long as its antennae and shows a short appendage ventrally.

The radula consists of exceptionally minute, acicular, sharp-pointed, horny prickles. There is no operculum Shell. The shell is thin, horny, smooth, oval, with a tumid body whorl, a rather high, subscalar, small-pointed, round-whorled, shallow-sutured conical spire, and a tumid lop-sided base, pointed at the columella, but with scarcely any snout. Sculpture. Longitudinals — there are close-set fine hairlike lines of growth.

Kernite, also known as rasorite is a hydrated sodium borate hydroxide mineral with formula . It is a colorless to white mineral crystallizing in the monoclinic crystal system typically occurring as prismatic to acicular crystals or granular masses. It is relatively soft with Mohs hardness of 2.5 to 3 and light with a specific gravity of 1.91. It exhibits perfect cleavage and a brittle fracture.

The crystals tend to be long thin blades that typically form radial aggregates, and sometimes fans and tufts. The aggregates are variable and may be spikey in appearance, dense and ball-like, or form worm-like growths. Tight acicular radiating clusters and sphericules are common forms. Thomsonite occurs with other zeolites in the amygdaloidal cavities of basaltic volcanic rocks, and occasionally in granitic pegmatites.

Crystals have been found up to 2 cm long, though most are smaller. They are typically bladed, elongated along the c axis and flattened perpendicular to the b axis. They also occur as acicular crystals, in spherical or tufted aggregates and as fibrous or drusy masses. The crystals are a characteristic carmine red colour, hence the name, and they are also red in transmitted light.

Wollastonite has industrial importance worldwide. It is used in many industries, mostly by tile factories which have incorporated it into the manufacturing of ceramic to improve many performance parameters, and this is due to its fluxing properties, freedom from volatile constituents, whiteness, and acicular particle shape.Deer, Howie and Zussman. Rock Forming Minerals; Single Chain Silicates, Vol. 2A, Second Edition, London, The Geological Society, 1997.

There is also a thermal arrest for the duration of the change of phase during which the temperature of the system does not change. The resulting solid macrostructure from a eutectic reaction depends on a few factors. The most important factor is how the two solid solutions nucleate and grow. The most common structure is a lamellar structure, but other possible structures include rodlike, globular, and acicular..

Derriksite is a very rare uranium mineral with the chemical formula Cu4(UO2)(SeO3)2(OH)6•H2O. It is a secondary mineral that contains copper, uranium and the rarer selenium. It is a bright green to duller bottle green colour. Its crystal habit is acicular, it is most likely to be found along with the uranyl selenium mineral demesmaekerite, but derriksite is much rarer than demesmaekerite.

Celsian shows a c(001) perfect cleavage and a b(010) good cleavage, which marks the difference with its polymorph paracelsian which has a [110] indistinct cleavage. There are different crystals habits like adularia, larger, stout crystals (Spencer, 1941), and long, slender to acicular. It is usually colorless and transparent with a pearly to non-fluorescent luster. The density is about 3.31 to 3.33 g/cm3.

Thaumasite is a calcium silicate mineral, containing Si atoms in unusual octahedral configuration, with chemical formula Ca3Si(OH)6(CO3)(SO4)·12H2O, also sometimes more simply written as CaSiO3·CaCO3·CaSO4·15H2O. It occurs as colorless to white prismatic hexagonal crystals, typically as acicular radiating groups. It also occurs as fibrous masses. Its Mohs hardness is 3.5 and it has a specific gravity of 1.88 to 1.90.

The formations of colimaite have been described as hedgehog–like particles due to the acicular habit of extremely fine needles forming the aggregates. The size of these aggregates range from 10 to 100 µm. The needles themselves have been measured up to 50 µm in length and 20 µm in width. Although colimaite belongs to the orthorhombic crystal class, their crystallographic forms were not observed.

The name is derived from natron (), the Greek word for soda, in reference to the sodium content, and lithos (), meaning stone. Needle stone or needle-zeolite are other informal names, alluding to the common acicular habit of the crystals, which are often very slender and are aggregated in divergent tufts. The crystals are frequently epitaxial overgrowths of natrolite, mesolite, and gonnardite in various orders.

Serandite is transparent to translucent and is normally salmon-pink, light pink, rose-red, orange, brown, black, or colorless; in thin section, it is colorless. Octahedrally bonded Mn(II) is the primary contributor to the mineral's pink colors.Manning, p. 357. Crystals of the mineral can be prismatic to acicular and elongated along [010], bladed, blocky, or tabular and flattened on {100}, occur as a radiating aggregate, or have massive habit.

Antarcticite is an uncommon calcium chloride hexahydrate mineral with formula: CaCl2·6H2O. It forms colorless acicular trigonal crystals. It is hygroscopic and has a low specific gravity of 1.715. As its name implies, it was first described in 1965 for an occurrence in Antarctica where it occurs as crystalline precipitate from a highly saline brine in Don Juan Pond, in the west end of Wright Valley, Victoria Land.

Rutilated quartz as gemstone Rutilated quartz is a variety of quartz which contains acicular (needle-like) inclusions of rutile. It is used for gemstones. These inclusions mostly look golden, but they also can look silver, copper red or deep black. They can be distributed randomly or in bundles, which sometimes are arranged star-like, and they can be sparse or dense enough to make the quartz body nearly opaque.

George-ericksenite is a mineral with the chemical formula Na6CaMg(IO3)6(CrO4)2(H2O)12. It is vitreous, pale yellow to bright lemon yellow, brittle, and features a prismatic to acicular crystal habit along [001] and somewhat flattened crystal habit on {110}. It was first encountered in 1984 at the Pinch Mineralogical Museum. One specimen of dietzeite from Oficina Chacabuco, Chile had bright lemon-yellow micronodules on it.

Like all ductile iron, ADI is characterized by its spheroidal graphite nodules spaced within the matrix. These nodules reduce microsegregation of solutes within the material. For ADI, the material has been austempered such that the matrix is transformed into ausferrite, or a mixture of acicular ferrite and austenite. The microstructure is used to classify ADI into grades, which depend on the heat treatment process and not the composition of the material.

Niter is a colorless to white mineral crystallizing in the orthorhombic crystal system. It usually is found as massive encrustations and efflorescent growths on cavern walls and ceilings where solutions containing alkali potassium and nitrate seep into the openings. It occasionally occurs as prismatic acicular crystal groups, and individual crystals commonly show twinning. Niter and other nitrates can also form in association with deposits of guano and similar organic materials.

Species of Parahololepidella are long-bodied, with 130 or more segments and 60 or more pairs of elytra, which continue to the end of the body. The eyltra are smooth and very small, leaving most of the parapodia and dorsum uncovered. The neuropodia have a sub-acicular process, and the notochaetae are more slender than neurochaetae, none of which are bidentate. Cephalic peaks are also present on the prostomium.

Fluorellestadite occurs as acicular or hexagonal prismatic, poorly terminated crystals, and as fine- grained aggregates.John J. Jambor and Jacek Puziewicz (1989) New Mineral Names American Mineralogist 74: 500, abstract of Chesnokov, Bazhenova and Bushmakin (1987) Zapiski Vses. Mineralog, Obshch 116:743 (in Russian) Crystals are transparent and aggregates are translucent. Material from Crestmore, California, is light rose-red or yellow in color, and typically occurs in a matrix of blue calcite.

Barium Ferrite is used in tape drives and floppy disks. Barium ferrite is used in applications such as recording media, permanent magnets, and magnetic stripe cards (credit cards, hotel keys, ID cards). Due to the stability of the material, it is able to be greatly reduced in size, making the packing density much greater. Earlier media devices utilized doped acicular oxide materials to yield the coercivity values necessary to record.

To the north follows a 10 centimeter wide band of white, powdery mylonite very rich in pyromorphite and crocoite. Next comes a 5 centimeter wide quartz band in boxwork facies, that is also very rich in the secondary minerals pyromorphite and crocoite. The crocoite appears skeletal and the pyromorphite acicular. The lode terminates on its north side with a 20 centimeter wide quartz band strongly mineralized in galena and sphalerite.

Brochantite is a sulfate mineral, one of a number of cupric sulfates. Its chemical formula is Cu4SO4(OH)6. Formed in arid climates or in rapidly oxidizing copper sulfide deposits, it was named by Armand Lévy for his fellow Frenchman, geologist and mineralogist A. J. M. Brochant de Villiers. Crystals of brochantite can range from emerald green to black-green to blue-green, and can be acicular or prismatic.

Protea decurrens grows up to 50 cm in diameter and 60 cm in height. It is suffrutescent; the main trunk of the plant is found burrowing below the ground like a thick root, sending up a number of branches which can grow from prostrate on the ground to ascending. The plant flowers from the base of these branches at ground level. The linear to acicular-shaped leaves are 1.4mm in width, but in length.

Rutile also shows a screw axis when its octahedra are viewed sequentially."Rutile Structure", Steven Dutch, Natural and Applied Sciences, University of Wisconsin – Green Bay. Rutile crystals are most commonly observed to exhibit a prismatic or acicular growth habit with preferential orientation along their c axis, the [001] direction. This growth habit is favored as the {110} facets of rutile exhibit the lowest surface free energy and are therefore thermodynamically most stable.

Sharma et al. utilized acicular spacers and achieved porosities up to 60% where pores were undistorted. In samples employing fine particles, porosities up to 70% were achievable before noting distortion in the pores. However, the bimodal pore distribution observed in coarse-spacer samples showed to be beneficial in terms of mechanical properties in that higher compressive strengths were observed, beyond those that might exist due to the inverse relationship of porosity and compressive strength alone.

The Francon quarry, Montréal, Québec. Strontianite is very common at the Francon Quarry, in a great variety of habits. It is a late stage mineral, sometimes found as multiple generations. It is found as translucent to opaque, white to pale yellow or beige generally smooth surfaced spheroids, hemispheres and compact spherical and botryoidal aggregates to 10 cm in diameter, and as spheres consisting of numerous radiating acicular crystals, up to 1 cm across.

The simple inflorescences are arranged with one per axil with spherical flower-heads containing 15 to 20 light golden flowers that turn orange-brown when dry. After flowering linear yellow woodyseed pods form that are around in length and around wide. The mottled seeds within the pods have an ovate to oblong shape and are about in length. The phyllodes resemble those of Acacia tetragonophylla and the acicular phyllode variant of Acacia maitlandii.

It is also an important constituent of amphibolites formed by metamorphism of basalt. Actinolite is an important and common member of the monoclinic series, forming radiating groups of acicular crystals of a bright green or greyish-green color. It occurs frequently as a constituent of greenschists. The name (from Greek ἀκτίς, ἀκτῖνος/aktís, aktînos, a 'ray' and λίθος/líthos, a 'stone') is a translation of the old German word Strahlstein (radiated stone).

Acanthochitona zelandica, along with other species of chiton such as Notoplax violacea, have some of the simplest valve structure of all known chitons. The dorsal layer, or tegmentum, is composed of one spherulitic sublayer, one crossed lamellar sublayer, and a ventral acicular sublayer. A. zelandica is the only currently known chiton that utilizes two different crossed lamellar structures. Photo of the eight individual chiton dorsal valves, which overlap but allow flexibility for locomotion.

Malachite is a copper carbonate hydroxide mineral, with the formula Cu2CO3(OH)2. This opaque, green-banded mineral crystallizes in the monoclinic crystal system, and most often forms botryoidal, fibrous, or stalagmitic masses, in fractures and deep, underground spaces, where the water table and hydrothermal fluids provide the means for chemical precipitation. Individual crystals are rare, but occur as slender to acicular prisms. Pseudomorphs after more tabular or blocky azurite crystals also occur.

Todorokite occurs as spongy banded and reniform (kidney-shaped) aggregates composed of minute lathlike crystals. The crystals are flattened parallel to the plane containing the a and c crystal axes, and elongated parallel to the c axis. Minerals of the hollandite-cryptomelane and romanèchite groups also have fibrous or acicular habits and two perfect cleavages parallel to the fiber axis. Todorokite is dark brown to brownish black in color and brown in transmitted light.

Metalasia is also found in KwaZulu-Natal, Free State, Eastern Cape and Lesotho. The leaves of Metalasia muricata are some 6 mm long, in tufts or fascicled, closely packed about the stem, acicular or needle-like, sharp- tipped, greenish-grey and may be either glabrous or woolly. Flowers range from white to pink or purple, are bisexual, and produce fruits or cypselae which in this genus are ribbed nutlets with bristly pappi. The greyish bark is slightly striated.

Plancheite is a chain silicate (inosilicate), with double chains of silica tetrahedra parallel to the c crystal axis. It occurs as sprays of acicular or fibrous radial clusters, with fibers extended parallel to the chains, i.e. along the c crystal axis; it can also form tiny tabular or platy crystals. It is a member of the orthorhombic crystal class m m m (2/m 2/m 2/m), which is the most symmetrical class in the orthorhombic system.

Ardaite occurs as 50 µm fine-grained aggregates of acicular crystals associated with galena, pyrostilpnite, anglesite, nadorite, and Cl-bearing robinsonite and semseyite, in the Madjarovo polymetallic ore deposit in Bulgaria. Ardaite has a hardness of 2.5 to 3 on Mohs scale and a density of approximately 6.44. The type locality is the Madjarovo polymetallic ore deposit in the Rhodope mountains.See the Collection of Minerals at the National Natural History Museum, Sofia, BulgariaSee the Madjarovo deposit at Mindat.

Abnormal grain growth observed in Rutile TiO2, induced by the presence of a zircon secondary phase. #Rutile (TiO2) frequently exhibits a prismatic or acicular growth habit. In the presence of alkali dopants or a solid state ZrSiO4 dopant, rutile has been observed to crystallise from a parent anatase phase material in the form of abnormally large grains existing in a matrix of finer equiaxed anatase or rutile grains. #Al2O3 with silica and/or yttria dopants/impurities has been reported to exhibit undesirable AGG.

Tempering involves a three-step process in which unstable martensite decomposes into ferrite and unstable carbides, and finally into stable cementite, forming various stages of a microstructure called tempered martensite. The martensite typically consists of laths (strips) or plates, sometimes appearing acicular (needle-like) or lenticular (lens-shaped). Depending on the carbon content, it also contains a certain amount of "retained austenite." Retained austenite are crystals which are unable to transform into martensite, even after quenching below the martensite finish (Mf) temperature.

These structure and composition match perfectly those found on other certified panels of Peter Bruegel. Moreover, it is noticeable that the wood charcoal particles are very peculiar, being very long and acicular, exactly the same as those found only in The Census from the same Museum. This related work by Joos de Momper includes the ploughman and angler, but Icarus is still in flight, with wax drops falling. Recently, a study of the underdrawing using infrared reflectography has been published.

The core may be surrounded by an electron-dense tunic. The entire microthrix is enveloped by a plasma membrane, the external layer of which is referred to as the glycocalyx. Two distinct sizes of microtriches are recognised: those < or = 200 nm in basal width, termed "filitriches", and those >200 nm in basal width, termed "spinitriches". Filitriches are considered to occur in three lengths: papilliform (< or = 2 times as long as wide), acicular (2-6 times as long as wide), and capilliform (>6 times as long as wide).

The shrub typically grows to a height of and has a spreading habit. It has slightly ribbed and terete branchlets that are densely covered with straight spreading hairs and have acicular and persistent stipules with a length of . Like most species of Acacia it has phyllodes rather than true leaves. The sessile, rigid and evergreen phyllodes have a widely elliptic to oblong shape and are inequilateral with a length of and a width of and have three to four distant and raised main nerves.

Body long, with numerous segments (50 to more than 100) and numerous pairs of elytra on segments 2, 4, 5, then on alternate segments to 23 and on every third segment thereafter. The prostomium is anteriorly rounded (without peaks) and the lateral antennae are inserted terminoventrally. Parapodia with elongate acicular lobes with both acicula penetrating epidermis. The notochaetae are stout, with distinct rows of spines and blunt tips; the neurochaetae are unidentate (lack a secondary tooth at the tips) (see Barnich & Fiege, 2003 for more detailed diagnosis).

Type I, or IEC I, ferric or 'normal' cassettes were historically the first, the most common and the least expensive; they dominated the prerecorded cassette market. Magnetic layer of a ferric tape consists of around 30% synthetic binder and 70% magnetic powder - acicular (oblong, needle-like) particles of gamma ferric oxide (γ-Fe2O3), with a length of to . Each particle of such size contains a single magnetic domain. The powder was and still is manufactured in bulk by chemical companies specializing in mineral pigments for the paint industry.

Gabbro is generally coarse grained, with crystals in the size range of 1 mm or larger. Finer grained equivalents of gabbro are called diabase (also known as dolerite), although the term microgabbro is often used when extra descriptiveness is desired. Gabbro may be extremely coarse grained to pegmatitic, and some pyroxene-plagioclase cumulates are essentially coarse grained gabbro, some may exhibit acicular crystal habits. Gabbro is usually equigranular in texture, although it may be porphyritic at times, especially when plagioclase oikocrysts have grown earlier than the groundmass minerals.

The leucite-hearing dike- rocks are members of the tinguaite and monchiquite groups. The leucite tinguaites are usually pale grey or greenish in color and consist principally of nepheline, alkali feldspar and aegirine. The latter forms bright green moss-like patches and growths of indefinite shape, or in other cases scattered acicular prisms, among the feldspars and nephelines of the ground mass. Where leucite occurs, it is always euhedral in small, equant, many-sided crystals in the ground mass, or in larger masses which have the same characters as the pseudoleucites.

Desert roses are most often bladed, exhibiting the familiar shape of a rose, and almost always have an exterior druse. Desert roses are almost always unattached to a matrix or base rock. Gypsum flowers are most often acicular, scaly, stellate, and lenticular. Gypsum flowers most often exhibit simple twinning (known as contact twins); where parallel, long, needle-like crystals, sometimes having severe curves and bends, will frequently form “ram’s horns”, "fishtail", "arrow/spear-head", and "swallowtail" twins. Selenite crystals can also exhibit “arrow/spear-head” as well as “duck-bill” twins.

Wollastonite occurs as bladed crystal masses, single crystals can show an acicular particle shape and usually it exhibits a white color, but sometimes cream, grey or very pale green. The streak of wollastonite is white, its Mohs hardness is 4.5–5 and specific gravity is 2.87–3.09. There are more than one cleavage planes for it, there is a perfect cleavage on , good cleavages on , and , and an imperfect cleavage on . It is common for wollastonite to have a twin axis [010], a composition plane (100), and rarely to have a twin axis [001].

Connellite is a rare mineral species, a hydrous copper chloro-sulfate, Cu19(OH)32(SO4)Cl4·3H2O, crystallizing in the hexagonal system. It occurs as tufts of very delicate acicular crystals of a fine blue color, and is associated with other copper minerals of secondary origin, such as cuprite and malachite. Its occurrence in Cornwall, England, was noted by Philip Rashleigh in 1802, and it was first examined chemically by Prof Arthur Connell FRSE in 1847, after whom it is named. The type locality is Wheal Providence at Carbis Bay in Cornwall.

Smith, pp. 387–388 ; Austempering: The austempering process is the same as martempering, except the quench is interrupted and the steel is held in the molten salt bath at temperatures between 205 °C and 540 °C, and then cooled at a moderate rate. The resulting steel, called bainite, produces an acicular microstructure in the steel that has great strength (but less than martensite), greater ductility, higher impact resistance, and less distortion than martensite steel. The disadvantage of austempering is it can be used only on a few steels, and it requires a special salt bath.

The Lovozero Massif is an area with an igneous mountain range, home to various types of minerals such as eudialyte, loparite, and natrosilitite. Crystallographically, zorite belongs in the orthorhombic group, which has 3 axes, a, b, and c that are of unequal lengths (a≠b≠c) that form 90° with each other. It also belongs in the point group 2/m2/m2/m. The state of aggregation for zorite is acicular. Zorite has perfect cleavage along the planes {010} and {001}, while having poor cleavage along the plane {110}.Fleischer, M. (1973) New Mineral Names.

So, AFt has a higher molar volume than AFm because of its 32 H2O molecules. During months, or years, after young concrete cooling, AFt crystallizes very slowly as small acicular needles and can exert a considerable crystallization pressure on the surrounding hardened cement paste (HCP). This leads to the expansion of concrete, to its cracking, and it can ultimately lead to the ruin of the affected structure. The characteristic feature of delayed ettringite formation (DEF) is a random honeycomb cracking similar to this of the alkali-silica reaction (ASR).

Recent authors have recognized this genus as nonmonophyetic, rejecting that the genus is a natural grouping. Two unnamed groups are distinguished by accessory tooth plates, which are either very elongated and bearing molar-like teeth, or are oval shaped or subtriangular and bearing acicular (needle-like) or conic teeth. A. jatius lacks these tooth plates, but has been included in this genus based on its adipose fin and lateral line. The recognition of Arenarius as a junior synonym of Arius is tentative and needs to be further investigated.

CrO2 was first prepared by Friedrich Wöhler by decomposition of chromyl chloride. Acicular chromium dioxide was first synthesized in 1956 by Norman L. Cox, a chemist at E.I. DuPont, by decomposing chromium trioxide in the presence of water at a temperature of 800 K and a pressure of 200 MPa. The balanced equation for the hydrothermal synthesis is: :3 CrO3 \+ Cr2O3 → 5 CrO2 \+ O2 The magnetic crystal that forms is a long, slender glass-like rod — perfect as a magnetic pigment for recording tape. When commercialized in the late 1960s as a recording medium, DuPont assigned it the tradename of Magtrieve.

Finely crystallized specimens have been obtained from the Friedrichssegen mine in Lahnstein in Rhineland-Palatinate, Johanngeorgenstadt in Saxony, Stříbro in the Czech Republic, Phoenixville in Pennsylvania, Broken Hill in New South Wales, and several other localities. Delicate acicular crystals of considerable length were found long ago in the Pentire Glaze mine near St Minver in Cornwall. Cerussite is often found in considerable quantities, and has a lead content of up to 77.5%. Lead(II) carbonate is practically insoluble in neutral water (solubility product [Pb2+][CO32−] ≈ 1.5×10−13 at 25 °C), but will dissolve in dilute acids.

Dendritic clinopyroxenes have spectacular textures including 'feathery' and 'swallowtail' varieties. The differentiated flows are separated into a cumulate layer at the base, and a spinifex layer at the top of each flow. The cumulate layers form by downwards sinking of olivine and chromite crystals through the lava, and have a thick layer of equant cumulate olivine overlain by a thin layer of large, skeletal 'hopper' olivine crystals. The spinifex layers form by growth of skeletal crystals from the top of the flow, and contain a range of textures and mineral assemblages, including random olivine spinifex and acicular clinopyroxene layers.

Abnormal or discontinuous grain growth leads to a heterogeneous microstructure where a limited number of grains grow much faster than the rest. Abnormal or discontinuous grain growth, also referred to as exaggerated or secondary recrystallisation grain growth, is a grain growth phenomenon through which certain energetically favorable grains (crystallites) grow rapidly in a matrix of finer grains resulting in a bimodal grain size distribution. In ceramic materials this phenomenon can result in the formation of elongated prismatic, acicular (needle-like) grains in a densified matrix with implications for improved fracture toughness through the impedance of crack propagation.

Use of filler metals is required to introduce alloying materials that serve to form oxides that promote the nucleation of acicular ferrite. The HAZ is still a concern that must be addressed with proper preheat and weld procedures to control the cooling rates. Slow cooling rates can be as detrimental and rapid cooling rates in the HAZ. Rapid cooling will form untempered martensite; however, very slow cooling rates caused by high preheat or a combination of preheat and high heat input from the weld procedures can create a very brittle martensite due to high carbon concentrations that form in the HAZ.

Like other types of dinosaur eggs, the shell of Guegoolithus is made up of tightly packed crystalline units. The shell is single-layered, but the shell units appear to be have two distinct layers because they exhibit a radiating acicular crystal structure near the base (the inner edge of the eggshell), but form a tabular ultrastructure on the upper third of the eggshell. The surface of the eggshell exhibits sagenotuberculate ornamentation (nodes and ridges forming a net-like pattern, with pits and grooves in betweenCarpenter, K. 1999. Eggs, Nests, and Baby Dinosaurs: A Look at Dinosaur Reproduction (Life of the Past).

Olivenite is a copper arsenate mineral, formula Cu2AsO4OH. It crystallizes in the monoclinic system (pseudo-orthorhombic), and is sometimes found in small brilliant crystals of simple prismatic habit terminated by domal faces. More commonly, it occurs as globular aggregates of acicular crystals, these fibrous forms often having a velvety luster; sometimes it is lamellar in structure, or soft and earthy. A characteristic feature, and one to which the name alludes (German, Olivenerz, of A. G. Werner, 1789), is the olive-green color, which varies in shade from blackish-green in the crystals to almost white in the finely fibrous variety known as woodcopper.

It is monoclinic m with space group Cc, but crystals are pseudotetragonal. Scolecite, like natrolite and mesolite, usually occurs as acicular (needle-like) and fibrous aggregations. It has nearly the same angles between the crystal faces as does natrolite, but natrolite is orthorhombic and scolecite is monoclinic. The etched figures (figures that arise from the action of a solvent on a crystal face, and indicate its true symmetry) and the pyroelectric character of scolecite show that it crystallizes with a plane of symmetry, but no axis of symmetry, that is to say it belongs to the hemihedral class of the monoclinic system.

In applied mathematics, a weighted planar stochastic lattice (WPSL) is a structure that has properties in common with those of lattices and those of graphs. In general, space-filling planar cellular structures can be useful in a wide variety of seemingly disparate physical and biological systems. Examples include grain in polycrystalline structures, cell texture and tissues in biology, acicular texture in martensite growth, tessellated pavement on ocean shores, soap froths and agricultural land division according to ownership etc. The question of how these structures appear and the understanding of their topological and geometrical properties have always been an interesting proposition among scientists in general and physicists in particular.

No mantle glands visible. This species can be characterised by the pattern of yellow-orange lines on the back and flanks, the absence of mantle glands and the acicular form of the rodlets of the labial armature. The structure of the radula teeth, which show a progressive growth along the row, makes it possible to differentiate it from Felimare gofasi, which also does not have mantle glands and whose outer lateral teeth are smaller than the inner ones. The lack of yellow pigment in the rhinophores allows the visual differentiation of this species from other animals of the North Atlantic with two lines on the back.

Eventually Faden noticed that certain specimens had needle-like, acicular hairs along the midvein on the leaves' upper surfaces, while others had mainly or only hook-hairs. Once sorted into two piles based on this character, Faden noticed that the plants with needle- like hairs also had all of their leaves clasping the stem, appendaged seeds, and capsules with a bulging apex, while those with hook-hairs only had leaves towards the tip clasping, unappendaged seeds, and broader capsules lacking an apical bulge. These characters proved sufficient for consistently separating both live and herbarium specimens. Neither Commelina imberbis nor Commelina mascarenica is most closely related to Commelina lukei.

Antlerite is a greenish hydrous copper sulfate mineral, with the formula Cu3(SO4)(OH)4. It occurs in tabular, acicular, or fibrous crystals with a vitreous luster. Originally believed to be a rare mineral, antlerite was found to be the primary ore of the oxidised zones in several copper mines across the world, including the Chuquicamata mine in Chile, and the Antler mine in Arizona, US from which it takes its name. It is chemically and optically similar in many respects to other copper minerals such as malachite and brochantite, though it can be distinguished from the former by a lack of effervescence in hydrochloric acid.

Niebla limicola is distinguished by a hemispherical thallus lying loose on soil without a central holdfast (terricolous), divided into variously shaped branches, partly narrow in length and prismatic in cross section, and partly flattened and dilated from which short acicular bifurcating branchlets arise, the thallus up to 10 cm high and 15 cm across. The species (N. limicola) also recognized by containing salazinic acid (without triterpenes), and by a relatively thin cortex, (0-)45–75 µm thick, appearing to erode on dilated parts of branches; the thinner cortex evidently related to the contorted appearance of the branches in addition to the medulla being partly hollow (fistulose). The species (N.

Above Tc, the structure is tetragonal, like rutile . In the monoclinic phase, the V4+ ions form pairs along the c axis, leading to alternate short and long V-V distances of 2.65 Å and 3.12 Å. In comparison, in the rutile phase the V4+ ions are separated by a fixed distance of 2.96 Å. As a result, the number of V4+ ions in the crystallographic unit cell doubles from the rutile to the monoclinic phase. The equilibrium morphology of rutile particles is acicular, laterally confined by (110) surfaces, which are the most stable termination planes. The surface tends to be oxidized with respect to the stoichiometric composition, with the oxygen adsorbed on the (110) surface forming vanadyl species.

Niebla arenaria is recognized by a hemispherical thallus similar to the reindeer lichen Cladonia rangiferina, loosely attached to soil without a holdfast, intricately divided into narrow tubular prismatic branches shortly bifurcate near branch tips, the tips usually with black dot-like pycnidia, and by containing the lichen substance salazinic acid. It sometime forms pure colonies along sandy shores of bays and peninsulas, possibly as a result of the black-tipped branchlets breaking off and reproducing. Similar species are Niebla brachyura, distinguished by containing the lichen substance hypoprotocetraric acid, Niebla pulchribarbara, distinguished by containing protocetraric acid, and Niebla limicola, that differs by the broad flattened curled (crispate) branches near base from which short bifurcate acicular branchlets develop.

Palaeontology exhibits and reserves in drawers, Muséum d'Angers The Muséum d'Angers has important collections of paleontology ( fossils, including palaeobotany, paleozoology and paleoichnology) tracing the history of life since the Cambrian, 500 million years ago. The Maine-et-Loire fossils come mainly from local Cretaceous tuffeau limestone and Tertiary faluns, but also from fossiliferous Armorican levels such as Ordovician or Devonian. A composite skeleton of the Miocene fossil sirenian Metaxytherium medium, an ancestor of the extant dugong, is a major asset of the palaeontological collections. Mineralogy ( samples, of which are from Maine-et-Loire) and petrography (600 samples) include a collection of slates, a monumental block of sharp acicular quartz, samples of native gold and meteorites.

Studtite, chemical formula [(UO2)O2(H2O)2]·2(H2O) or UO4·4(H2O), is a secondary uranium mineral containing peroxide formed by the alpha-radiolysis of water during formation.Studtite: The first structure of a peroxide mineral It occurs as pale yellow to white needle-like crystals often in acicular, white sprays. Studtite was originally described by Vaes in 1947Annales de la Société Géologique de Belgique - 1947 - pp B212 to B226- J.F. Vaes - Six nouveaux minéraux d'urane provenant de Shinkolobwe (Katanga) - from specimens from Shinkolobwe, Katanga Copper Crescent, Katanga (Shaba), Democratic Republic of Congo, and has since been reported from several other localities. The mineral was named for Franz Edward Studt, an English prospector and geologist who was working for the Belgians.

Vermilacinia zebrina, which often has a yellowish green thallus, frequently occurs with V. cephalota in California. It differs by the branches appearing slender throughout, usually with regular occurring black spots or bands, and usually without depsidones. Vermilacinia leonis, which has a flaccid thallus much like cooked spaghetti, is found mainly south of the Vizcaíno Peninsula in Baja California, and also reported to occur in Chile. Two other sorediate species, described in the genus Niebla, one of which is similar to some forms of V. cephalota, was distinguished by dot-like (“punctiform”) soralia that develop on terminal acicular branchlets; another has a flattened thallus similar to Ramalina lacera, but referred to Niebla by the presence of the depside methyl 3,5 dichlorolecanorate;Sipman, H.J.M. 2011.

This examination was carried out by attaching two acicular crystals to the surface of a disk with epoxy and then examining them with a CAMECA SX-50 electron microprobe. One of the crystals had the (100) surface facing up, and the other crystal had a growth face of the form (110) facing up. The microprobe was operating in wavelength- dispersive mode at 15 kV and ran various currents from 20 nA to 0.5 nA. The CAMECA SX-50 has three spectrometers and the samples were examined in the sequence (Na, Cl, I), then (Mg, S, Ca). When the crystal was exposed to the electron beam for the first 200 seconds, the counts per second on each element varied greatly which indicates that the crystals are extremely unstable in the electron beam.

The red pitahaya at the Chiyai market, Taiwan The flowers in Rome Dragonfruit stems are scandent (climbing habit), creeping, sprawling or clambering, and branch profusely. There can be 4–7 of them, between 5 and 10 m or longer, with joints from 30–120 cm or longer, and 10–12 cm thick; with generally three ribs; margins are corneous (horn-like) with age, and undulate. Areoles, that is, the small area bearing spines or hairs on a cactus, are 2 mm across with internodes 1–4 cm. Spines on the adult branches are 1–4 mm long, being acicular (needle-like) to almost conical, and grayish brown to black in colour and spreading, with a deep green epidermis. The scented, nocturnal flowers are 25–30 cm long, 15–17 cm wide with the pericarpel 2.5–5 cm long, about 2.5 cm thick, bracteoles ovate, acute, to 2.5 to less than 4 cm long; receptacle about 3 cm thick, bracteoles are linear-lanceolate, 3–8 cm long; outer tepals lanceolate-linear to linear, acuminate (tapering to a point), being 10–15 cm long, 10–15 mm wide and mucronate (ending in a short sharp point).

Stems scandent, clambering or sprawling, branching, producing aerial roots, stiff, to 1-2(-5) m long, 2–3 cm thick; ribs 4-6 or more, later terete, acute; areoles 1,5–2 mm on Ø, reddish brown at first, later greyish brown, internodes 1,5-2,5 cm; spines 6-8, 1 mm long, acicular, white or yellowish, later blackish, radial spines 5-6 central spines 1-2, basally 0,25 mm in Ø above the swollen bases, apically attenuate-conical, circular in cross section, the bulbous bases 0,5 mm in Ø, hairlike spines none; epidermis light green, somewhat shining. Flowers produced from areoles near tip, 8–14 cm long, 7-8,5 cm in Ø, nocturnal but stays open for 2 2–3 days (John Ellis, UK), tepals rotate; pericarpel covered with spines, but no hairs, bracteoles small, triangular, reddish; receptacle ca 5 cm long, green, with clusters of 7-12 spines, 4–5 mm long, brownish, but no hairs; outer tepals 5,5–6 cm, narrowly oblong, acute, brownish; inner tepals 7,5 cm, 11 mm wide, narrowly oblong, acute, white, sometimes with pink base or pinkish throughout; stamens white, much shorter than inner tepals; style yellow, stigma lobes 9-11. Fruit globular, yellow, covered densely with yellowish spines.