Zoisite


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Related to Zoisite: epidote

zoisite

[′zȯi‚sīt]
(mineralogy)
Ca2 Al3Si3O12(OH) A white, gray, brown, green, or rose-red orthorhombic mineral of the epidote group consisting of a basic calcium aluminum silicate and occurring massive or in prismatic crystals.

Zoisite

 

(after the Slovenian enlightener S. Zois [1747–1819]), a mineral of the class of nesosilicates, with a chemical composition of Ca2Al3 [SiO4] [Si2O7](OH). The typical impurities are Fe3+, Fe2+, Mn, Mg, and, less frequently, Cr, V3+, Na, and K. The structure of zoisite is based on single and twinned tetrahedrons of [SiO4]4– radicals. Zoisite crystallizes in the orthorhombic system, forming prismatic crystals with striations on the faces. It is usually found in granular, columnar, fibrous, and occasionally radiated aggregates. The color is gray or greenish. Manganese-containing zoisite, called thulite, is pink; the chromium-containing variety is bright green. The vanadium-containing zoisite, called tanzanite, exhibits dichroism between dark blue and red violet. Zoisite has a hardness of 6–6.5 on Mohs’ scale and a density of 3,250–3,370 kg/m3.

Zoisite is a rock-forming mineral for several metamorphosed shales and hydrothermally altered basic igneous rocks (it is the chief component of saussurite). It is also found in crystal-bearing veins, skarns, corundum plagioclasites (anorthosites), and other formations. Certain transparent colored varieties are used in jewelry-making.

References in periodicals archive ?
Eclogites are fine-grained rocks consisting of garnet porphyroblasts set in a matrix of omphacite (25%), amphibole (hornblende or barroisite) (20%), plagioclase and zoisite; rutile often rimmed by titanite occurs as the main accessory mineral phase, phengite is quite rare whereas quartz is nearly absent.
It's a gem-quality zoisite ranging in colour from deep blue to burgundy red through violet and purple and several gem hunters have claimed they were the first to find it.
Wilson and partners are exploring the possibility of extracting a mineral called zoisite from the mountain, which may, or may not, have a bizarre application.
UBAIDULLAH QADRI: Pakistan has enormous wealth of expensive gems such as ruby, emerald, tourmaline, garnet, topaz, peridot, aquamarine, spinel, pargasite, diopside, moonstone, pink topaz, sapphire, zircon, feldspar, agate, serpentine jade, epidote, pink beryl (morganite), purple beryl, sphene, zoisite, lapis lazuli, turquoise, and kunzite etc.
Of course, the blues (and purple-blues, and some yellows) are tanzanite zoisite, and the greens are "tsavorite" grossular and chromium-rich diopside.
The REE in clastic sediments are concentrated in detrital accessory minerals, mainly phosphates (notably monazite and apatite for LREE and xenotime for HREE), minor silicates (notably allanite, titanate, and zoisite for LREE, garnet and zircon for HREE), and adsorbed to clays (especially HREE).
(a) The long vowel sound is preceded and succeeded by a short 's' sound Long A Sevssel (the name of 2 villages on the upper Rhone), sayst Long E deceased, caecitis Long I incisor, syce (an Indian horse groom) Long O saussurite (variety of the mineral zoisite), society Long U disuse
That's why you'll find Zababa, Zincenite, Zippeite, Zoisite, Zoubekite, Zunyite, Zussmanite, Zvyagintsevite, Zweiselite in the Z section of the alphabet.
Other minor constituents of marbles can include fluorite, apatite, brucite, laumontite, olivine, scheelite, spinel, zoisite, and magnetite.
Primary ores, assigned to the gold-sulphide formation, are represented by metasomatically altered rocks composed of carbonates, quartz, micas, chlorite and zoisite. The discovery of Olimpiadninskoe is one of the proofs for the high potential of finding further deposits in the Yenisei goldfield.