| 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 Sphalerite
Sphalerite is one of the very few minerals that has a total of six directions of cleavage, and occurs in many different colors. It is an unusual rare gemstone which is craved for by people as it possesses more brilliance than diamonds.
Color: Orange, yellow, brown, green
Categories: semi-precious stone
Chemical Composition: ZnS
Crystal Group: Cubic
Refractive Index: 2.37
Hardness: 3.5-4
Density: 4.05
Occurrence: Spain, Mexico
|  Natural Star Sapphire
A star sapphire is a lovely gem that exhibits a six pointed star because of the intersection of six thin intersecting inclusions. When the gem is lit from above, the inclusions become quite visible and the star shape appears.A powdery grey-blue star sapphire is the centerpiece of a ring from the Art Deco period.
Color: Blue, green blue, violet, blue, black, brown, pink.
Categories: semi-precious stone
Chemical Composition: AL2O3
Crystal Group: Hexagonal
Refractive Index: 1.759-1.778
Hardness: 9
Density: 4
Occurrence: Sri Lanka, Burma, India, East Africa, Ankarana-Madagascar, Thailand.
|  Natural Topaz
Topaz is a silicate mineral most often found in igneous rocks of felsic composition. It is a common gemstone that has been used for centuries in jewelry. Gem quality topaz most commonly occurs in nature as a colorless crystal. It is a very popular gemstone.
Color: colorless, blue, yellow-brown, pinkish orange, red-orange, red-brown, tan.
Categories: semi-precious stone
Chemical Composition: AL(F,OH)2SIO4
Crystal Group: Orthorhombic
Refractive Index: 1.629 - 1.637
Hardness: 8
Density: 3.52 - 3.56
Occurrence: Brazil, Sri Lanka, Nigeria, Germany, Australia, Japan, Russia, Ireland, Zimbabwe.
|  Natural Tourmaline
Tourmaline is actually a group of several different minerals which have similar crystal structures, but complex and variable chemical formulas. Tourmaline is the most varicolored of all gemstones. It occurs in all colors, but red, green, and multicolored are its most famous gem colors.
Color: blue, bluish green, green, greenish blue, green-blue or blue-green, greenish yellow, orangy red, red, red-orange or orange-red, red-purple or purple-red, slightly purplish red, slightly yellowish green, strongly purplish red, strongly yellowish green, very slightly bluish green, yellowish green, yellow-green or green-yellow, colorless, brown, pink
Categories: semi-precious stone
Chemical Composition: (NaCa)(LI,MgFe,Al)9B3Si6(O,OH)31
Crystal Group: Hexagonal
Refractive Index: 1.624(+.005, -.005) - 1.644(+.006, -.006)
Hardness: 7-7.5
Density: 3.06 (.05, +.15)
Occurrence: Brazil, East Africa, Nigeria, Madagascar, U.S.A.
|  Natural Triplite
Triplite is a rare fluoro-hydroxide phosphate mineral that forms in phosphate rich granitic pegmatites and high temperature hydrothermal veins. The name is from the Greek triplos for triple, in reference to the three cleavage directions. It is a very gemstones and few cut stones have been ever reported.
Color: brightly coloured (brown, salmon, flesh-red)
Categories: semi-precious stone
Chemical Composition: (Mn,Fe2+)2(PO4)(F,OH)
Crystal Group: Monoclinic
Refractive Index: 1.650 - 1.680
Hardness: 5 - 5.5
Density: 3.44 - 3.90
Occurrence: the Shigar Valley, Pakistan; China; France, Bavaria, Germany; Kimito, Finland; Karibib, Namibia; Maine, and Connecticut, Arizona and Colorado in the United States.
|  Natural Zircon
Zircon is a mineral belonging to the group of nesosilicates. It is one of the heaviest gemstones, which means that it will look smaller than other varieties of the same weight. Zircon occurs in a wide range of colours,the most popular colour is blue zircon. The wide variety of colours of zircon, its rarity, and its relatively low cost make it a popular collector's stone.
Color: Brown, blue, red, orange, white, green
Categories: semi-precious stone
Chemical Composition: ZrSiO4
Crystal Group: Tetragonal
Refractive Index: 1.780-1.984
Hardness: 7.5
Density: 4.00-4.73
Occurrence: Ceylon, Burma,France, Norway, East Africa,Australia, SE Asia.
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