Infobox mineral name Meionite boxwidth boxbgcolor image Meionite Quartz 53866.jpg imagesize alt caption Meionite scapolite crystals cross shaped in a quartz matrix, 7.2 x 4.0 x 3.0 cm. Worcester County, Massachusetts . category Tectosilicate Scapolite group formula Ca sub 4 sub Al sub 6 sub Si sub 6 sub O sub 24 sub CO sub 3 sub strunz 09.FB.15 symmetry 4 m Dipyramidal unit cell a 12.179 1 , c 7.571 1 molweight color Colorless, white, grey, pink, violet, blue, yellow, orange brown, brown colour habit system Tetragonal twinning cleavage Distinct good on 100 110 fracture Irregular uneven, conchoidal tenacity Brittle mohs 5 6 luster Vitreous, resinous, pearly streak White diaphaneity Transparent, opaque gravity 2.74 2.78 density polish opticalprop refractive birefringence pleochroism 2V dispersion extinction length fast slow fluorescence absorption melt fusibility diagnostic solubility impurities alteration other prop1 prop1text references ref http www.mindat.org min 2627.html Mindat.org ref ref http www.webmineral.com data Meionite.shtml Webmineral.com ref ref http www.handbookofmineralogy.com pdfs meionite.pdf Handbook of Mineralogy ref Meionite is a Silicate minerals silicate mineral belonging to the scapolite group with the formula Ca sub 4 sub Al sub 6 sub Si sub 6 sub O sub 24 sub CO sub 3 sub . Some samples may also contain a sulfate group. It was first discovered in 1801 on Mt Somma, Vesuvius , Italy . References Reflist Category Tectosilicates Category Calcium minerals Commons Silicate mineral stub ar fa fr M ionite it Meionite he nl Meioniet uk ... more details
Infobox mineral name Marialite boxwidth boxbgcolor image imagesize alt caption category Silicate mineral formula Na sub 4 sub Al sub 3 sub Si sub 9 sub O sub 24 sub Cl strunz dana symmetry Tetragonal 4 m unit cell a 12.06 , c 7.572 3 Z 2 color Colorless, white, grey pink, violet, blue, yellow, brown, orange brown, pale green or reddish colour habit Typically flat, pyramidal striated crystals massive, granular system Tetragonal crystals are usually prismatic twinning cleavage Distinct on 100 and 110 fracture Uneven to conchoidal tenacity Brittle mohs 5 &ndash 6 luster Vitreous, pearly, resinous streak White diaphaneity Transparent to opaque gravity 2.55&ndash 2.74 density 2.5&ndash 2.62 g cm sup 3 sup polish opticalprop Uniaxial refractive n sub sub 1.539&ndash 1.550 n sub sub 1.532&ndash 1.541 birefringence 0.007 0.009 pleochroism 2V dispersion extinction length fast slow fluorescence absorption melt fusibility diagnostic solubility impurities alteration references ref name Klein Klein, C., and Dutrow, B. 2007 The 23rd Edition of the Manual of Mineral Science, 675 p. John Wiley and Sons, Inc. Hoboken, New Jersey, U.S.A. ref ref name HBM http rruff.geo.arizona.edu doclib hom marialite.pdf Handbook of Mineralogy ref ref name Mindat http www.mindat.org min 2575.html Mindat.org ref ref name Webmin http www.webmineral.com data Marialite.shtml Webmineral data ref Marialite is a silicate mineral with a chemical composition of Na sub 4 sub Al sub 3 sub Si sub 9 sub O sub 24 sub Cl ref name Mindat ref name Webmin if a pure endmember or Na sub 4 sub AlSi sub 3 sub O sub 8 sub sub 3 sub Cl sub 2 sub ,CO sub 3 sub ,SO sub 4 sub with increasing meionite content. ref name Klein Marialite is a member of the scapolite group and a solid solution exists between marialite and meionite , the calcium endmember. ref name Klein It is a rare mineral usually used as a collector s stone. It has a very rare but attractive gemstones and cat s eye. ref http www.galleries.com minerals si ... more details
meionite is found as colorless glassy crystals in the ejected limestone blocks of Monte Somma, Vesuvius ... composition between 2.7 meionite and 2.5 marialite . The scapolites are especially liable to alteration ... with an igneous magma . Even meionite the variety richest in soda occurs in this association, being ... more details
Infobox mineral name Amarantite boxwidth boxbgcolor image Amarantite Javir e Sagand, Yazd Province, Iran.jpg imagesize alt caption category Sulfate minerals formula Fe sup 3 sup sub 2 sub O pipe SO sub 4 sub sub 2 sub 7H sub 2 sub O strunz 07.DB.30 dana symmetry unit cell V 674.09 Calculated from Unit Cell molweight color Amaranth Red to Brownish Red, Orange Red colour habit system triclinic twinning cleavage Perfect on 010 and 100 , perfect. fracture tenacity Brittle mohs 2 luster Vitreous streak Lemon Yellow diaphaneity Transparent gravity density 2.189 2.286 g cm sup 3 sup polish opticalprop refractive birefringence pleochroism Visible 2V dispersion extinction length fast slow fluorescence absorption melt fusibility diagnostic solubility impurities alteration other prop1 prop1text references Amarantite is an amaranth red to brownish mineral ref name mindat with the general formula of Fe sup 3 sup sub 2 sub O SO sub 4 sub sub 2 sub 7H sub 2 sub O. ref http www.mindat.org show.php?id 182&ld 2 ref The name comes from the Greek word which means amaranth, an imaginary undying red flower, in allusion to its color. ref http webmineral.com data Amarantite.shtml ref Amarantite is triclinic, which means crystallographically, it has only one symmetry fold. It must be rotated 360 degrees to be exactly the same. Due to it being triclinic it falls into the biaxial optical class, the axis degrees do not equal 90 degrees and the sides of each axis are not the same length. ref Alpers, C.N., Jember, J.L. and, Nordstrom, D.K. 2000 Reviews in Mineralogy and Geochemistry volume 40 Sulfate Minerals Crystallography, Geochemisrty, and Environmental Significance ref Amarantite is anisotropic, ref name mindat http www.mindat.org min 182.html ref which means, the velocity of light varies with crystallographic direction, and, thus, there is more than one refractive index. ref name klein Klein,C and Hurlbut, Jr.C.S., 1985 Marialite meionite series. Manual of Mineralogy 20th ed. , ... more details
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