Amber | Hydrocarbon | Amorphous | Baltic-yellow, Sicilian-Reddish yellow, Rumanian-Brown, Burmes-Yellow to brown | 2.5 | 1.08 | 1.54 |
Andalusite | Al2O3SiO2 | Rhombic | Green, greenish brown withredish tints | 7.5 | 3.15 | 1.64 |
Apatite | Ca4(CaF(PO4)3 | Hexagonal | Yellow, blue, green | 5 | 3.21 | 1.638 |
Axinite | Ca,Al,Mg | Triclinic | Clove brown, violet | 7 | 3.28 | 1.685 |
Benitoite | BaOTiO2 3SiO2 | Hexagonal | Saphire blue to colourless | 6.5 | 3.67 | 1.78 |
Beryl | 3BeO.Al2O36SiO2 | Hexagonal | Emerald-green | 7.5 | 2.71 | 1.575 |
| | | Aquamarine-Pale blue to bluish-green | 7.5 | 2.69 | 1.575 |
| | | Golden beryl (Heliodor) -Yellow | 7.5 | 2.68 | 1.57 |
| | | Pink beryl (Morganite) -Rose-pink, also colourless | 7.5 | 2.8 | 1.59 |
Blende | ZnS | Cubic | Brown, yellow, orange, black.Transparent to opaque green | 3.5 | 4.09 | 2.37 |
Brazilianite | NaAl3(OH)4(PO4)2 | | Greenish-yellow, Transparent or translucent | 5.5 | 2.99 | 1.612 |
Chrysoberyl | BeO.Al2O3 | Rhombic | Alexandrite-Green in day-light, red in artificial light | 8.5 | 3.71 | 1.75 |
| | | Cat's-eye (Cymophane) - Greenish or brownish yellow translucent and chatoyant | 8.5 | 3.71 | 1.75 |
| | | Also yellow, greenish yellow, colourless and brown | | | |
Corundum | Al2O3 | Hexagonal | Ruby-Red | 9 | 3.99 | 1.765 |
| | Trigonal | Saphire-Blue.Also colourless, yellow, pink, green and violet | 9 | 3.99 | 1.765 |
| | | Star ruby, star saphire-Translucent, showing asterism | | | |
Cassiterite | SnO2 | Tetragonal | Colourless to very dark brown | 6.5 | 6.8 to 7.00 | 2.045 |
Danburite | CaO.B2O3 2SiO2 | Rhombic | Pale yellow, colourless | 7 | 3 | 1.633 |
Datolite | Calcium borosilicate Monoclinic | | Colourless or very pale green, also as cloudy nodules in various colours | 5 | 2.99 | 1.648 |
Diamond | C | Cubic | Colourless, shades of yellow and brown, Rarely blue, red, green | 10 | 3.52 | 2.418 |
Diopside | CaO.MgO 2SiO2 | Monoclinic | Pale green to dark green.Sometime chatoyant | 5 | 3.9 | 1.69 |
Enstatite | MgO.SiO2 | Rhombic | Green, sometime chatoyant | 5.5 | 3.27 | 1.67 |
Epidote | Silicate of Ca & Al Monoclinic | | Dark brownish green | 6.5 | 3.45 | 1.75 |
Euclase | Be(AlOH)SiO4 | Monoclinic | Pale green or blue.Sometimes yellow, colourless | 7.5 | 3.1 | 1.665 |
Feldspar Group | K2O.Al2O3 6SiO2 | Monoclinic | Yellow orthoclase | 6 | 2.56 | 1.525 |
Orthoclase | | | Moonston-Colourless with white or bluish sheen | 6 | 2.57 | 1.53 |
Microcline | " " | Triclinic | Amazonite-Bluish green, translucent to opaque | 6 | 2.56 | 1.53 |
| | | Oligoclase-Pale yellow | 6 | 2.64 | 1.545 |
Plagioclases | Na & Ca Aluminosilicate,Triclinic | | Labradorite-Grey with play of colour | 6 | 2.7 | 1.565 |
| | | Sunston-Spangled reddish | 6 | 2.64 | 1.54 |
Fibrolite | Al2O3.SiO2 | Rhombic | Pale blue | 7.5 | 3.25 | 1.665 |
Fluorspar | CaF2 | Cubic | Purple, blue, green, yellow, pink, colourless.Blue John or Derbyshire spar-M-banded | 4 | 3.18 | 1.434 |
Garnet group | | Cubic | | | | |
Almandine | 3FeO.Al2O3.3SiO2 Cubic | | Purplish red | 7.5 | 3.9-4.2 | 1.76-1.81 |
Pyrope | 3MgO.Al2O3.3SiO2 Cubic | | Deep blood red | 7.25 | 3.7-3.9 | 1.73-1.76 |
Grossular | 3CaO.Al2O3.3SiO2 Cubic | | Hessonite-Orange-brown, also green, pink etc.massive grossular | 7.25-7 | 3.65-3.49 | 1.74-1.73 |
Andradite | 3CaO.Fe2O3.3SiO2 Cubic | | Demantoid-Green/ Topazolite-Yellow | 6.5 | 3.85 | 1.89 |
Spessartite | 3MnO.Al2O3.3SiO2 Cubic | | Orange or yellow. Flame red | 7 | 4.16 | 1.8 |
Haematite | Fe2O3 | Hexagonal | Gun-metal black in crystals or when polished | 6 | 5.1 | very high |
Hambergite | Beryllium borate | Orthorhombic | Colourless transparent | 7.5 | 2.35 | 1.587 |
Idocrase(Vesuvianite)Ca & Fe silicate, Tetragonal | | | Brown, yellow, green; transparent | 6.5 | 3.38 | 1.7 |
| | | Californite--Green massive; translucent | 5.5 | 3.3 | 1.7 |
Iolite | Mg,Fe,Silicate&Al. Rhombic | | Blue | 7 | 2.59 | 1.535 |
Jadeite | Na2O.Al2O3.4SiO2 Monoclinic | | Green, white, brown, mauve; translucent | 7 | 3.3 | 1.66 |
Kornerupine | Mg,Al silicate | Rhombic | Green, brownish green, yellow; transparent | 6.5 | 3.32 | 1.675 |
Kyanite | Al2O3.SiO2 | Triclinic | Blue; sometimes green or colourless | 4 to 7 | 3.69 | 1.72 |
Lapis Lazuli | Complex silicate,containing sulphur Blue; opaque | | blue;opaque | 5.5 | 2.8 | 1.5 |
| Fe,Mg,Al phosphate,Monoclinic | | Blue; translucent to opaque | 5.5 | 3.1 | 1.62 |
Malachite | Cu2(OH)2CO3 | Monoclinic | Green, mottled; opaque | 4 | 3.8 | 1.78 |
Nephrite | Ca,Mg,Fe silicate, Monoclinic | | Green, white;translucent to opaque | 6.5 | 2.96 | 1.62 |
Opal | SiO2+nH2O | Amorphous | Fire opal-orange.Seldom shows play of colours | 6 | 2 | 1.45 |
| | | White opal-Play of colour on pale, translucent background | 6 | 2.1 | 1.45 |
| | | Black opal-Play of colour on dark background | 6 | 2.1 | 1.45 |
| | | Water opal-Play of colour within almost colourless stone | 6 | 2 | 1.45 |
Pearl | CaCO3 with conchyolin and water | olin and water | Oriental-White or creamy | 3.5 | 2.71 | NA |
| | | Australian-Silvery white | 3.5 | 2.74 | NA |
| | | Venezuelan-Translucent white | 3.5 | 2.7 | NA |
| | | Black-Bronze or gunmetal colours | 3.5 | 2.65 | NA |
| | | Blue-Lead grey, due to dark nucleus | 3.5 | 2.6 | NA |
| | | Freshwater-Dull.iridescent | 3.5 | 2.7 | NA |
| | | Conch-Pink;no pearly lustre | 3.5 | 2.85 | NA |
| | | Clam- Black; no pearly lustre | 3.5 | 2.65 | NA |
Peridot (Olivine) 2(Mg,Fe)O.SiO2 | | Rhombic | Green, Brownish or yellowish green | 6.5 | 3.34 | 1.67 |
Phenakite | 2BeO.SiO2 | Hexagonal | Commonly colourless | 7.5 | 2.96 | 1.662 |
Prehnite | Ca,Al Silicate | Rhombic | Pale green or greenish yellow; translucent | 6 | 2.87 | 1.63 |
Pyrites | FeS2 | Cubic | Brassy yellow metallic lustre; Opaque | 6 | 4.9 | NA |
Quartz | SiO2 | Hexagonal | Rock-crystal- Colourless | 7 | 2.65 | 1.548 |
| | | Amethyst-Purple | | | |
| | | Citrine-Yellow | | | |
| | | Cairngorm-Brown | | | |
| | | Morion-Smoky quartz | | | |
| | | Rose quartz-Pink, Cloudy | | | |
| | | Aventurine-Green, spangled, also brown | | | |
| | Trigonal | Quartz Cat's-eye-Pale brown chatoyant | 7 | 2.65 | 1.548 |
| | | Tiger's-eye or crocidolite-Golden brown chatoyant | | | |
| | | Rutilated quartz-Colourless with included rutile | | | |
Chalcedony | (Cryptocrystaline quartz | | Chalcedony-Unbanded grey | 7 | 2.6 | 1.53 |
Group | | | Cornelian-Red | | | |
| | | Chrysoprase-Apple green | | | |
| | | Agate-Concentric bands of various colours | | | |
| | | Onyx-Streight bands | | | |
| | | Sardonyx-Red and white bands | | | |
Rhodochrosite | MnCO3 | Hexagonal | (Trigonal) Rose red to pink; translucent | 4 | 3.6 | 1.71 |
Rhodonite | MnO.SiO2 | Triclinic | Rose red; translucent | 6 | 3.6 | 1.72 |
Scapolite | Group of complex | Tetragonal | Pale yellow ;transparent | 6 | 2.7 | 1.57 |
| silicates etc. | | Pink chatoyant. | | | |
| | | Violet chatoyant | 6 | 2.63 | 1.545 |
Scheelite | CaWO4 | Tetragonal | Colourless, yellow, orange | 5 | 5.9 to6.1 | 1.93 |
Sinhalite | Mg(AlFe)BO4 | Rhombic | Pale yellow to dark brown or greenish brown, Transparent | 6.5 | 3.48 | 1.685 |
Smithsonnite | ZnCO3 | Hexagonal | (Trigonal)Yellow or apple green;translucent | 5 | 4.35 | 1.73 |
Sphene (Titanite) CaO.TiO2.Sio2 | | Monoclinic | Yellow, green , brown | 5.5 | 3.53 | 1.96 |
Spinel | MgO.Al2O3 | Cubic | Red, pink, pale greyish blue, dark greenish blue, shades of reddish purple | 8 | 3.6 | 1.717 |
| | | Ceylonite or Pleonaste, Black, opaque | 8 | 3.8 | 1.78 |
| | | Gahnospinel-Shades of blue containing varying proportions of zinc | 8 | to 4.06 | to1.754 |
Spodumene | Li2O.Al2O3.4SiO2 | Monoclinic | Kunzite-Lilac | 7 | 3.18 | 1.67 |
| | | Hiddenite-Green , also yellow | | | |
Topaz-Fluo-or hydroxy silicate of | | Rhombic | Colourless, Blue | 8 | 3.56 | 1.62 |
| aluminium | | Yellow, pink, orange, brown | | 3.53 | |
Tourmaline | Complex boro-silicate of Al, Mg,Fe, | | (Trigonal) Achroite--Colourless | 7 | 3.05 | 1.63 |
| alkalis etc. | Hexagonal | Rubelite--Red, deep pink | | | |
| | | Indicolite--Deep inky blue.Also green, pink, yellow, brown, black & particoloured | | | |
Turquoise | Hydrous phosphate of aluminium and | | Dark to pale sky blue, pale greenish blue; Translucent to opaque | 6 | 2.6 | 1.61 |
| copper | | | | to 2.8 | |
Zircon | ZrO2.SiO2 | Tetragonal | Colourless, blue, orange, red, yellow, golden brown | 7.5 | 4.69 | 1.95 |
| | | Green and shades of green | 6.5 | 4 to 4.5 | 1.79 upward |