| Gemstone Chart |
 Natural Sillimanite
Sillimanite is an alumino-silicate mineral with the chemical formula Al2SiO5. Sillimanite is a very rare trimorph and it has a common variety called fibrolite.
Color: violet blue, grey green, colorless, brown, green,
Categories: semi-precious stone
Chemical Composition: Al2OSiO4
Crystal Group: Orthorhombic
Refractive Index: 1.658 - 1.678
Hardness: 6 - 7.5
Density: 3.25
Occurrence: France, Madagascar, U.S.A., Sri Lanka, Burma. Kenya
|  Natural Tanzanite
Tanzanite is a rare gem which has been celebrated as one of the most exciting finds of the 20th century. Manuel D¡¯Souza discovered the gem in 1967 in Tanzania. Because tanzanite is relatively soft, it is not usually set in necklaces and earrings, so the tiara is truly a rarity.
Color: Blue, Blue Purple, Green, Pink.
Categories: semi-precious stone
Chemical Composition: Ca2(Al,OH)Al2(SIO4)
Crystal Group: Orthorhombic
Refractive Index: 1.688 - 1.707
Hardness: 6-7
Density: 3.30 (+.10, -.10)
Occurrence: Tanzania
|
|
|Register|Sign in|Customization
+'/&media=https://www.etoolsage.com/../images/eTools.gif'+'&description='+encodeURIComponent(document.title),'_blank','toolbar=yes, location=yes, directories=no, status=no, menubar=yes, scrollbars=yes, resizable=no, copyhistory=yes, width=600, height=450,top=100,left=350');void(0) "Pinterest")
