| 词条 | Narsarsukite |
| 释义 |
| name = Narsarsukite | category = Silicate mineral | image = Narsarsukite-20220.jpg | imagesize = | alt = | caption = 1.3 cm crystal of narsarsukite from Mont Saint-Hilaire | formula = Na4(Ti,Fe)4[Si8O20](O,OH,F)4.[1] | molweight = | strunz = 9.DJ.05 | dana = | system = Tetragonal | class = Dipyramidal (4/m) H-M symbol: (4/m) | symmetry = I4/m | unit cell = a = 10.72, c = 7.95 [Å]; Z = 4 | color = Honey to lemon-yellow, reddish brown, brownish gray, tan, pink; may be green from inclusions; may show color zoning | colour = | habit = Occurs as flat tabular to equant, striated crystals In divergent, radiating groups; massive | twinning = | cleavage = Good on {100} and {110} | fracture = Uneven to subconchoidal | tenacity = Brittle | mohs = 5.5 - 7 | luster = Vitreous, pearly on {110} | streak = White | diaphaneity = Transparent to translucent | gravity = 2.64-2.83 | density = | polish = | opticalprop = Uniaxial (+) | refractive = nω = 1.609 nε = 1.630 | birefringence = δ = 0.021 | pleochroism = Weak; O = colorless to yellow; E = colorless to honey-yellow | 2V = | dispersion = | extinction = | length fast/slow = | fluorescence = | absorption = | melt = | fusibility = | diagnostic = | solubility = | impurities = | alteration = | other = | references = [1][2][3] }}Narsarsukite is a rare silicate mineral with chemical formula Na2(Ti,Fe3+)Si4(O,F)11[1] or Na4(Ti,Fe)4[Si8O20](O,OH,F)4.[2] It was first described in 1900 for an occurrence in the Narsarsuk pegmatite in the Ilimaussaq intrusive complex of West Greenland.[2] It has also been reported from a syenite which intruded limestone in the Sweetgrass Hills, Montana, and within hornfels and marble xenoliths in the alkalic intrusive of Mont Saint-Hilaire, Quebec.[1] It occurs associated with aegirine, microcline, albite, elpidite, epididymite, taeniolite, pectolite, calcite, galena and quartz.[1] References1. ^1 2 3 Handbook of Mineralogy {{silicate-mineral-stub}}2. ^1 2 3 Narsarsukite on Mindat.org 3. ^Narsarsukite data on Webmineral 2 : Inosilicates|Tetragonal 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。