| 词条 | Cuspidine |
| 释义 |
| name = Cuspidine | image = | alt = | caption = | category = Sorosilicate | formula = Ca4(Si2O7)(F,OH)2 | molweight = | strunz = 9.BE.17 | dana = | system = Monoclinic | class = Prismatic (2/m) (same H-M symbol) | symmetry = P21/c | unit cell = a = 10.93 Å, b = 10.57 Å, c = 7.57 Å; β = 110.11°; Z=4 | color = Colorless, tan, light brown, pale red | habit = Minute spearhead-shaped crystals, acicular, granular | twinning = Simple, lamellar, polysynthetic on {100} | cleavage = Good on {001} imperfect on {110} | fracture = Uneven | tenacity = Brittle | mohs = 5-6 | luster = Vitreous | streak = | diaphaneity = Transparent to translucent | gravity = 2.85-2.96 | density = | polish = | opticalprop = Biaxial (+) | refractive = nα = 1.586 - 1.594 nβ = 1.589 - 1.596 nγ = 1.598 - 1.606 | birefringence = δ = 0.012 | pleochroism = | 2V = Measured: 59° to 71° | dispersion = | extinction = | length fast/slow = | fluorescence = | absorption = | melt = | fusibility = | diagnostic = | solubility = | impurities = | alteration = | other = | references = [1][2][3] }} Cuspidine is a fluorine bearing calcium silicate mineral (sorosilicate) with formula: Ca4(Si2O7)(F,OH)2.[1] 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.[1][3] The name is from the Greek cuspis for spear from its characteristic crystal form.[1] Cuspidine occurs as crystals in tuff from Monte Somma. In the Franklin, New Jersey mine area it occurs in contact metamorphosed limestone. In Dupezeh Mountain, Iraq, it occurs in melilite bearing skarn. Associated minerals include augite, hornblende, diopside, grossular, biotite, phlogopite, monticellite, wollastonite, calcite, spinel, magnetite and perovskite.[3] References1. ^1 2 3 Cuspidine on Mindat.org 2. ^Cuspidine data on Webmineral 3. ^1 2 Cuspidine in the Handbook of Mineralogy 2 : Sorosilicates|Monoclinic minerals |
| 随便看 |
|
开放百科全书收录14589846条英语、德语、日语等多语种百科知识，基本涵盖了大多数领域的百科知识，是一部内容自由、开放的电子版国际百科全书。