Gemstone Identification Chart

Gemstone Identification Chart

Note: We have Tried our best to provide gemstone identification chart Which is available around website and collected from many sources from authentic books which referenced by GIA. To made Gemstone identification Easy. You Can use below search bar to find the specific gemstone by typing it’s gemstone name example “corundum”. You can also use the arrow mark to sort in various orders.

Refractive Index is the most important testing factor, so the values given for these are published in ascending order. The specific gravity values, rather less used in gem testing, in most cases increase with increasing refractive index and fall within limits into defined groups, and therefore may be readily found in the table. Where constants are outside the given range, or may not easily be found within that range; The word ‘to’ between figures implies variation in range, while ‘–’ indicates the greatest and least readings in doubly refractive stones. ‘I’ means isotropic, ‘U’ uniaxial, and ‘B’ Biaxial. Glass imitation stones commonly have refractive Index which lie between 1.50 and 1.70.

NameRefractive indexBirefringenceOptic signOptical characterHardnessSpecific gravityLusterColors
Sellaite1.378–1.3900.012PositiveU5 to 63.15VitreousColorless to white
Fluorite1.434I43.18VitreousAll Colors
Fire opal1.435 to 1.4551.97 to 2.06Subvitreous to waxyColorless, white, yellow, red, orange, green, brown, black, blue, pink
Opal1.44 to 1.46I5.5 to 61.98 to 2.20Subvitreous to waxyColorless, white, yellow, red, orange, green, brown, black, blue, pink
Silica glass1.46I62.21
Creedite1.460–1.4850.025 B3.52.71VitreousColorless, white, violet, orange
Thaumasite1.464– 1.500 to 1.468–1.5070.031 to 0.043 NegativeU3.51.88 to 1.90Vitreous to silky
Colorless, white, pale yellow
Sodalite1.48I5.5 to 62.15 to 2.35, usually 2.25 to 2.3Dull vitreous to greasy
Rich royal blue, green, yellow, violet, white veining common
Natrolite1.480–1.4930.013PositiveB5.52.20 to 2.25Vitreous, Silky, Pearly
White, colorless, sometimes pink
Obsidian1.48 to 1.51I52.33 to 2.42Vitreous
Deep black or blackish green
Moldavite1.48 to 1.54I5.52.34 to 2.39VitreousMossy green
Calcite1.486 –1.6580.172NegativeU32.71Vitreous to pearly on cleavage surfaces
Colorless or white, also gray, yellow, green,
Calcite(marble)1.486– 1.65832.71Vitreous to pearly on cleavage surfaces
Colorless or white, also gray, yellow, green,
Coral1.486 to 1.6580.1723.52.6 to 2.7Opaque White, Pink, Red, Black
Analcime1.487I5 to 5.52.20 to 2.29VitreousWhite, colorless, gray, pink, greenish, yellowish
Whewellite1.490 –1.6500.16PositiveB2.52.23Vitreous, PearlyWhite, yellow, brown,
Tektites1.49 to 1.53I52.36 to 2.51
Yugawaralite1.492 –1.5040.009PositiveB4.52.19 to 2.22Vitreous, PearlyColourless, white
Celluloid1.495 –1.510I1.51.36 to 1.42
Cellulose Acetate1.495–1.5051.51.29 to 1.40
Celluloid 1.495 to 1.510I1.5usually 1.36 to 1.80, 1.36 to 1.42
Haüyne1.496I5.5 to 6.52.4Vitreous to greasy
Blue, white, gray, yellow, green, pink
Tugtupite1.496–1.5020.006PositiveU62.36 to 2.57Sub-Vitreous, Waxy, Greasy, DullCommonly red, also white to pink, bluish white, greenish white
Perspex1.5I21.18 to 1.19
Lapis lazuli1.5I5.52.70 to 2.90dullBlue, mottled with white calcite and brassy pyrite
Mesolite1.50 (mean)0.001PositiveB52.29Vitreous, silky when fibrous
Colorless, white, gray, yellowish brown
Dolomite1.502– 1.6810.179NegativeU3.5 to 42.8 to 2.9Vitreous to pearly
White, gray to pink
Petalite1.504–1.5160.012PositiveB6 to 6.52.39 to 2.46Vitreous, pearly on cleavages
Colorless, grey, yellow, pink, to white
Ulexite1.51 (mean)0.02PositiveB11.65 to 2.00Vitreous; silky or satiny in fibrous aggregates
Colorless to white
Leucite1.51 (mean)0.001PositiveU5.5 to 62.45 to 2.50VitreousWhite to grey
Cancrinite1.51 (mean)0.022NegativeU62.42 to 2.50Vitreous, greasy, pearly
Grey-green, white, yellow, blue, orange, reddish
Poudretteite1.511 to 1.5320.021
PositiveU52.51
Vitreous (Glassy)
Colorless, Light pink
Scolecite1.512–1.5230.011NegativeB5 to 5.52.21Vitreous, silky when fibrous
Colorless white, pink, salmon, red or green
Magnesite1.515– 1.7170.202NegativeU3.5 to 4.53.00 to 3.12VitreousColorless, white, pale yellow, pale brown, faintly pink, lilac-rose
Pollucite1.517 to 1.525I6.52.85 to 2.94Vitreous to greasy
Usually colorless, also white, grey, pink, blue or violet
Sanidine1.518–1.5240.006NegativeB2.57 to 2.58Vitreous, pearly on cleavage
Colorless to white
Thomsonite1.52–1.540.028PositiveB5 to 5.52.3 to 2.4vitreous, pearly
colorless, white, beige,and pink
Orthoclase feldspar (moonstone)1.52–1.53 to 1.53–1.540.008NegativeB62.56 to 2.59Vitreous, pearly on cleavage surfaces
Colorless, greenish, greyish yellow, white, pink
Stichtite1.52–1.550.027NegativeU2.52.15 to 2.22Waxy to resinous
Lilac to rose-pink
Gypsum (alabaster)1.52–1.530.01PositiveB1.5 to 22.30 to 2.33Vitreous to silky, pearly, or waxy
Colorless to white; may be yellow, tan, blue, pink, brown, reddish brown or gray due to impurities
Microcline feldspar1.522–1.5300.008NegativeB6.52.56 to 2.58VitreousColorless
Yellow orthoclase feldspar1.522–1.5270.005NegativeB62.56VitreousGreen, Yellow
Milarite1.529–1.532 to 1.548–1.5510.003NegativeU5.5 to 62.46 to 2.61
Lepidolite1.530–1.5560.026NegativeB3.5 to 42.8 to 3.3 , usually 2.80 to 2.9Vitreous to pearly
Pink, purple, rose-red, violet-gray, yellowish, white, colorless
Iolite1.53–1.54 to 1.54–1.550.008 to 0.012NegativeB72.57 to 2.66,usually 2.57 to 2.61Greasy or vitreous
Blue, smoky blue, bluish violet; greenish, yellowish brown, gray; colorless to very pale blue in thin section
Aragonite1.530– 1.6850.155NegativeB3.5 to 42.93 to 2.95Vitreous, resinous on fracture surfaces
White, red, yellow, orange, green, purple, grey, blue and brown
Amazonite1.52 to 1.530.008Negative6 to 6.52.56 to 2.58VitreousBlue, Green, Purple, Gray, Multicolored
Meerschaum1.53 (mean)21.00 to 2.00
Chalcedony1.530 to 1.5390.004 (av.)NegativeB72.58 to 2.62Waxy, vitreous, dull, greasy, silky
Various
Pearl1.530 to 1.6851.553.5 to 42.20 to 2.78white, pink, silver, cream, brown, green, blue, black, yellow, and purple
Witherite1.532–1.6800.148NegativeB3.54.27 to 4.35Vitreous, resinous on fractures
Colorless, white, pale gray, with possible tints of pale-yellow, pale-brown, or pale-green
Apophyllite1.535–1.5370.002Pos/NegU4.5 to 52.30 to 2.50Vitreous; pearly
Usually white, colorless; also blue, green, brown, yellow, pink, violet
Bone1.542.52
Copal resin1.54I21.03 to 1.10
Vegetable ivory1.542.51.38 to 1.42
Dentine ivory1.542.25 to 2.51.70 to 1.98
Amber1.54I2 to 2.51.03 to 1.10
Nepheline1.540.004NegativeU5.5 to 62.55 to 2.65Vitreous - greasy
White, Gray, Brown, Brownish gray, Reddish white
Albite feldspar1.54 approx.0.011PositiveB6 to 6.52.62Vitreous, typically pearly on cleavages
White to gray, blueish, greenish, reddish; may be chatoyant
Soapstone1.54 approx.B1 to 22.7 to 2.8
Jasper1.54 approx.72.58 to 2.91VitreousWhite, Blue, Red, Green, Yellow, Orange, Brown, Gray, Black, Banded, Multicolored
Oligoclase feldspar (sunstone)1.542–1.5490.007NegativeB6 to 6.52.62 to 2.65Vitreous. Pearly on cleavage surfaces.Colorless, yellow, red, green, blue, and copper shiller
Quartz1.544–1.5530.009PositiveU72.65Vitreous – waxy to dull when massive
Colorless through various colors to black
Scapolite (pink1.544–1.5600.016NegativeU62.63VitreousWhite, Colorless, Yellow, Orange, Brown, Pink, Purple
Scapolite (yellow)1.548–1.5680.02NegativeU62.71VitreousWhite, Colorless, Yellow, Orange, Brown, Pink, Purple
Tortoise-shell and horn1.552.51.26 to 1.35
Charoite1.550–1.5590.009PositiveB5 to 62.54 to 2.68Vitreous to pearlyViolet, lilac, light brown
Pyrophyllite1.55– 1.601.52.8Pearly to dull
Brown green, brownish yellow, greenish, gray green, gray white
Saussurite1.55–1.706.52.7 to 3.4
Casein (protein plastic)1.55 to 1.56I2.51.32 to 1.34
Casein plastic1.55 to 1.56I2.251.32 to 1.34
Hambergite1.553 –1.625 to 1.559–1.6310.072PositiveB7.52.35VitreousColorless, pale gray, pale yellow
Beryllonite1.553–1.5620.009NegativeB5.5 to 62.80 to 2.85Vitreous to adamantine, may be pearly on {010}
Colorless, white to pale yellow
Synthetic emerald (flux melt)1.558–1.5630.003NegativeU7.52.65Opaque Black
Black coral1.563.51.34
Deer horn1.562.51.60 to 1.85
Serpentine (bowenite)1.56NegativeB2.5 to 42.5 to 2.7, 2.58 to 2.62Greasy, waxy, or silkyWhite, yellow, green, gray, brown, black, purple; sometimes multicolored, especially green and yellow.
Labradorite feldspar (yellow) 1.560–1.568 to 1.565–1.5730.008PositiveB6 to 6.52.68 to 2.69Vitreous to pearly on cleavages
Gray, brown, greenish, blue, yellow, colorless
Emerald1.56–1.57 to 1.59–1.600.006 to 0.007NegativeU7.52.69 to 2.75VitreousGreen shades to colorless
Variscite1.56 (mean)NegativeB52.4 to 2.6Vitreous to waxyGreen, blue green, yellow green and rarely red
Brazil (some)1.566–1.5710.0052.69
Bytownite feldspar1.567–1.5760.009NegativeB6 to 6.52.73Vitreous, pearly on cleavages
Colorless, white, gray
Chrysocolla1.575 - 1.585 0.023 - 0.050NegativeB2.5 - 3.51.9 - 2.4Vitreous to dullBlue, cyan or blue-green, green
Pseudophite1.570.003Pos/NegB2.52.60 to 2.85
Serpentine (williamsite)1.57NegativeB2.52.61Greasy, waxy, or silkyWhite, yellow, green, gray, brown, black, purple; sometimes multicolored, especially green and yellow.
Aquamarine1.570–1.575 to0.005 to 0.006NegativeU7.52.68 to 2.73VitreousBlue
Odontolite1.57– 1.63Vitreous53.00 to 3.10
Ophicalcite(Connemara marble)1.57 approx.3 to 42.7 approx.
Bastite1.57 to 1.58NegativeB3.5 to 42.5 to 2.7
Colombia (Chivor)1.571–1.5770.0062.69
Anhydrite1.571 –1.6140.043PositiveB3 to 3.52.90 to 2.98Pearly on {010}
vitreous to greasy on {001}
vitreous on {100}
Colorless to pale blue or violet if transparent; white, mauve, rose, pale brown or gray from included impurities
Augelite1.574–1.5880.014PositiveB52.7Vitreous, pearly on {110} cleavage
Colorless to white, may be yellowish to pale rose, greenish
Colombia (Muzo)1.578–1.5840.0062.71
Tanzania1.578–1.5850.0072.74Vitreous, pearly on cleavage surfaces
Blue, Violet
yellow and some pink beryls1.580–1.5862.68 to 2.73Vitreous to resinousGreen, blue, yellow, colorless, pink and others
Some white and pink beryls1.58–1.59 to1.59–1.600.008 to 0.009NegativeU7.52.80 to 2.90Vitreous to resinousGreen, blue, yellow, colorless, pink and others
Vivianite1.580– 1.6270.047PositiveB22.6Vitreous, pearly on the cleavage, dull when earthy
Colorless, very pale green, becoming dark blue, dark greenish blue, indigo-blue, then black with oxidation
Verdite1.58 (mean)32.80 to 2.99Vitreous, silky, pearly
Green
Russia and Brazil1.581–1.5880.0072.74
Catapleiite1.582– 1.6270.028PositiveU62.73 to 2.90Vitreous, DullDark brown, reddish brown, flesh red, yellowish red,colourless, light grey, beige to tan, light yellow, orange, light blue
Xonotlite1.583–1.5930.01PositiveB5 to 62.7Vitreous - SilkyColorless, Gray, Lemon white, Light gray, Pink.
Zambia1.583–1.5900.0072.74
Habachtal1.584–1.5910.0072.74
India1.585–1.5950.007 to 0.0102.73 to 2.74
Zimbabwe1.586–1.5930.0072.75
Transvaal1.586–1.5930.0072.75
Colemanite1.586 –1.6140.028PositiveB4.52.42VitreousColorless, white, yellowish, grey
Pakistan1.588–1.5950.0062.76
Polystyrene1.59I2.251.05
Larimar1.59 to 1.650.0384.5 to 62.70 to 2.90SilkyWhite, blue, green-blue, multicolored
Howlite1.59 (mean)0.02NegativeB3.252.58Subvitreous, glimmering
Colorless, Gray, White
Melinophane1.593– 1.6120.019NegativeU3.53VitreousColorless, shades of yellow. reddish.
Phosphophyllite1.595– 1.6160.021PositiveB3.53.1vitreousblue-green to colourless
Pectolite1.595 –1.6330.038PositiveB5 to 62.62 to 2.88Silky, vitreousColorless, whitish, grayish, yellowish
Wardite1.595 (mean)0.009PositiveU52.81VitreousWhite, colorless, pale green, blue-green, yellow-green, pale yellow, yellow pink.
Ekanite1.597I6 to 6.53.28Vitreous
Green, yellow, dark red
Eudialyte1.598– 1.602 to 1.610–1.6110.004PositiveU5 to 62.8 to 3.1VitreousRed, magenta, brown; also blue and yellow
Termolite1.599 to 1.6370.026NegativeB5 to 62.99 to 3.03Vitreous and silky
White, gray, lavender to pink, light green, light yellow
Nephrite1.60–1.63 to 1.62–1.65, mean 1.620.027NegativeB6.52.90 to 3.02dullTranslucent to opaque and often mottled. Light to dark green, yellow to brown, white, gray, black.
Rhodochrosite1.60 –1.820.22NegativeU43.50 to 3.65Vitreous to pearlyPink, rose-red, cherry-red, yellow, yellowish gray, cinnamon-brown, may be banded
Chondrodite1.60 (mean)PositiveB6.53.1 to 3.2Vitreous to Greasy
Yellow, orange, red or brown, rarely colorless
Vulcanite1.60 to 1.63I21.15 to 1.20Metallic
Pale to yellow bronze
Vulcanite (hard rubber)1.60 to 1.6321.15 to 1.20
Grandidierite1.602–1.6390.037NegativeB7.53Vitreous, Pearly
Bluish green
Brazilianite1.603–1.6230.02PositiveB5.52.980 to 2.995VitreousYellow, green, colorless
Sogdianite1.606–1.6080.002NegativeU6 to 72.76 to 2.90VitreousViolet, pale pink
Sugilite1.607–1.6100.004NegativeU5.5 to 6.52.74VitreousLight brownish-yellow, purple, violet, reddish violet, pale pink, colorless
Topaz1.610–1.6380.008 to 0.010PositiveB83.53 to 3.56VitreousColorless (if no impurities), blue, brown, orange, gray, yellow, green, pink and reddish pink
Prehnite1.61–1.640.03PositiveB62.8 to 2.95, usually 2.88 to 2.94Vitreous to pearly
Yellow-green, brown-yellow, gray, white and colorless
Persian and Egyptian Turquoise1.61–1.650.04PositiveB5.5 to 6approx. 2.8Waxy to subvitreous
Turquoise, Blue, blue-green, green
American Turquoise1.61–1.650.04PositiveB5.5 to 6approx. 2.6Waxy to subvitreous
Turquoise, Blue, blue-green, green
Turquoise1.61–1.650.04PositiveB5.5 to 62.6 to 2.85Waxy to subvitreous
Turquoise, Blue, blue-green, green
Herderite1.61 (mean)0.03PositiveB53VitreousColourless, pale yellow, greenish-white
Sugilite1.610 to 1.6070.003NegativeU6 to 6.52.74VitreousLight brownish-yellow, purple, violet, reddish violet, pale pink, colorless
Bakelite1.61 to 1.662.251.25 to 2.00 , usually 1.26 to 1.30
Gaspeite1.61 to 1.810.224.5 to 53.7Vitreous to dullPale green, apple-green, yellowish-green, bright green
Bakelite (higher if filled)1.61 to 1.662.51.25 to 1.30
Amblygonite1.611–1.6370.026PositiveB63.01 to 3.03Vitreous to pearly[Generally white or creamy, but can also be colorless or pale yellow, green, blue, beige, gray, brown or pink.
Hemimorphite1.612–1.6330.021PositiveB53.44Vitreous, adamantine, rarely silky
White, blue, greenish
Lazulite1.615–1.6450.036NegativeB5.53.1VitreousAzure-blue, sky-blue, bluish white, yellow-green, blue-green, rarely green
Wollastonite1.616–1.6310.015NegativeB4.5 to 52.8 to 2.9Vitreous or dull to pearly on cleavage surfaces
White, colorless or gray
Tourmaline1.616–1.634 to 1.630–1.6520.014 to 0.022NegativeU7 to 7.53.00 to 3.12Vitreous, sometimes resinous
Most commonly black, but can range from colorless, brown, violet, yellow, orange, blue, red, green, pink, or bi-colored, or even tri-colored.
Actinolite1.620–1.6420.022NegativeB5 to 5.53.05vitreous to dull
pale to dark green, yellowish green and black. White or grey when in asbestos
Smithsonite1.62– 1.850.23NegativeU54.30 to 4.35Vitreous, may be pearly
White, grey, yellow, green to apple-green, blue, pink, purple, bluish grey, and brown
Clinohumite1.623–1.651 to 1.632–1.6620.024 to 0.037PositiveB6 to 6.53.18Vitreous to resinous
Brownish to orange, yellow, red
Celestine1.625–1.6350.01PositiveB3.53.97 to 3.99Vitreous, pearly on cleavages
Colorless, white, pale blue, pink, pale green, pale brown, black
Datolite1.625–1.6690.044NegativeB52.9 to 3.00Vitreous, rarely subresinous on fracture surface
Colorless or white; may be grayish, yellow, green, red, pink
Friedelite1.629–1.6640.035NegativeU4 to 53.06 to 3.19Vitreous (Glassy)
an, brown, "beef steak"
Danburite1.630–1.6360.006NegativeB73Vitreous – greasy
Colourless, white, gray, brownish white, straw yellow
Apatite1.63–1.640.002 to 0.004NegativeU53.17 to 3.23Vitreous to subresinousTransparent to translucent, usually green, less often colorless, yellow, blue to violet, pink, brown.
Siderite1.633 –1.8730.24NegativeU3.5 to 43.83 to 3.88Vitreous, may be silky to pearly
Pale yellow to tannish, grey, brown, green, red, black and sometimes nearly colorless
Andalusite1.634–1.644 to 1.641–1.6480.007 to 0.011NegativeB7.253.15 to 3.17VitreousPink, violet, yellow, green, white, gray; in thin section, colorless to pink or green
Barite / Baryte1.636–1.6480.012PositiveB34.3 to 4.6Vitreous, Pearly
Colorless, white, light shades of blue, yellow, grey, brown
Jeremejevite1.639–1.6480.009NegativeU6.5 to 73.29–3.31VitreousColorless, white, yellowish, blue
Väyrynenite1.639–1.6670.026NegativeB53.23VitreousLight pink to rose-red, salmon pink, pale gray, brown
Eosphorite1.640–1.645 to 1.668–1.6800.028 to 0.035NegativeB4.53.1Vitreous, resinous
usually pale brown, golden brown, also medium brown to dark brown; occasionally pink, rose red
Jet1.64 to 1.68 2.5 to 4usually 1.20 to 1.30Velvety to waxy
Deep black, dark brown
Ludlamite1.650–1.689 to 1.653–1.6930.04PositiveB3 to 43.19Vitreous, pearly on cleavage
Apple-green to bright green
Malachite1.65– 1.900.25NegativeB43.74 to 3.95, usually 3.8Adamantine to vitreous; silky if fibrous; dull to earthy if massive
Bright green, dark green, blackish green, commonly banded in masses; green to yellowish green in transmitted light
Euclase1.652–1.6720.02PositiveB7.53.1VitreousColorless, white, pale green to deep yellowish green, greenish blue, pale blue to deep blue
Peridot1.654–1.6890.036PositiveB6.53.34Vitreous (glassy)
Yellow, to yellow-green, olive-green, to brownish, sometimes a lime-green, to emerald-ish hue
Phenakite1.654–1.6700.016PositiveU7.5 to 82.95 to 2.97VitreousColorless, yellow, pink, brown
Jadeite1.654–1.667, mean 1.660.013PositiveB73.30 to 3.36Subvitreous, pearly on cleavages
Apple-green, emerald-green, bluish green, leek-green,greenish white, white, may show green spots, rarely blue or violet; colorless in thin section. Often also banded.
Magnesioaxinite1.656–1.6680.012NegativeB6.5 to 73.18VitreousPale Blue to pale Violet; light Brown to light Pink
`
Fibrolite1.658–1.6780.02PositiveB6.5 to 73.25VitreousBlue, brown, colourless, green, grey
Sillimanite1.659 - 1.680 0.015 to 0.0116 to 7.53.25 +/-, 0.02, 0.11Vitreous to subadamantine, silky
Colourless or white to grey, also brown, yellow, yellow-green, grey-green, blue-green, blue; colourless in thin section
Spodumene1.660–1.6750.015PositiveB73.17 to 3.19Vitreous, pearly on cleavage
Highly variable: white, colorless, gray, pink, lilac, violet, yellow and green, may be bicolored; emerald green - hiddenite; lilac - kunzite; yellow - triphane
Serandite1.660–1.6880.028PositiveB4.5 to 53.32Vitreous, greasyPink, orange, red, tan, and brown. May oxidize brown or black upon exposure to air.
Boracite1.66 to 1.67I72.96Vitreous - adamantineColorless, white, gray, brown, orange, yellow, pale green, dark green, blue-green, or blue; colorless in transmitted light
Durangite1.662 –1.7120.05NegativeB53.97 to 4.07VitreousLight to dark
Enstatite1.663–1.6730.01PositiveB5.53.26 to 3.28Vitreous, pearly on cleavage
White, grey, green, yellow or brown - colorless in thin section.
Kornerupine1.665–1.678 to 1.668–1.6800.013NegativeB6.53.28 to 3.35VitreousColorless, white, grey, greenish, bluish, brown, black
Lawsonite1.665–1.6840.019PositiveB7 to 83.09Vitreous, greasy
Colorless, white, pale blue to grayish blue
Hypersthene1.67–1.68 to 1.71–1.730.010 to 0.020NegativeB5 to 63.4 to 3.5vitreous to pearly
gray, brown, or green
Diopside1.67 –1.700.03PositiveB5.53.29Vitreous to dull
Commonly light to dark green; may be blue, brown, colorless, white, grey
Sinhalite1.67 –1.710.038NegativeB6.53.47 to 3.49VitreousColourless, yellow-brown, green-brown, brown
Parisite1.671– 1.7720.01PositiveU4.54.33Vitreous - greasyBrown, brownish yellow, gray-yellow, grayish yellow, yellow, waxy yellow, colourless to yellow in transmitted light
Legrandite1.675 –1.7350.06PositiveB53.98 –4.04VitreousBright yellow, wax-yellow, colorless
Axinite1.675–1.6850.01NegativeB73.27 to 3.29VitreousReddish brown to yellow to colorless. Blue, violet, grey.
Dumortierite (massive)1.68 (mean)B73.26 to 3.41Vitreous to dull
Blue, greenish-blue, violet-blue, pale blue, red
Triphylite1.689–1.695 to 1.694–1.7020.006 to 0.008PositiveB4 to 53.42 to 3.52Vitreous–subresinous
Green–blue gray, brown–black
Rhodizite1.69I83.4Adamantine, VitreousColourless, white, greyish, yellowish; colourless in transmitted light
Willemite1.69– 1.720.028PositiveU5.53.89 to 4.18Vitreous to resinous
Colorless to white, gray, flesh-red, dark brown, honey-yellow, apple-green, blue
Zoisite1.692– 1.7000.008PositiveB63.35Vitreous, pearly on cleavage surfaces
White, gray, greenish brown, greenish gray, pink, blue, purple
Idocrase1.700–1.7120.005 (mean)Neg/PosU6.53.32 to 3.47Vitreous to resinous
Yellow, green, brown; colorless to white, blue, violet, bluish green, pink, red, black, commonly zoned
Thulite (zoisite)1.700–1.7060.006NegativeB63.09 to 3.12Vitreous, pearly on cleavage surfaces
Pink
Serendibite1.700–1.7430.006PositiveB6.5 to 73.42 to 3.52Vitreouspale yellow, blue-green, greyish blue, black
Chlorastrolite1.70 (mean)B5 to 63.1 to 3.5
Smaragdite1.70 approx.5 to 5.53.25VitreousEmerald green
Diaspore1.702–1.7500.048PositiveB6.5 to 73.30 to 3.35Adamantine, vitreous, pearly on cleavage faces
White, pale gray, colorless, greenish gray, brown, pale yellow, pink, purple; may exhibit color change
Arandisite1.704 approx.54Bright green
Sapphirine1.705–1.7110.006Neg/PosB7.53.40 to 3.58VitreousLight to dark blue or green, white, gray, pale red, yellow
Adamite1.710–1.759 to 1.742–1.7730.031 to 0.050PositiveB3.54.30 to 4.68VitreousPale yellow, honey-yellow, brownish yellow, reddish; rarely white, colorless, blue, pale green to green, may be zoned;
Spinel1.714 to 1.736I83.58 to 3.64VitreousVarious; red, pink, blue, lavender/violet, dark green, brown, black, clear
Kyanite directional1.715–1.7320.017NegativeB5 to 73.65 to 3.68Vitreous to pearly
Blue, white, rarely green, gray, yellow, pink, orange, and black, can be zoned
Taaffeite1.718–1.7220.004NegativeU83.60 to 3.61VitreousColorless, greyish violet, violet red, red, greenish, light green, pink violet, mauve
Massive grossular garnet1.72I7.253.36 to 3.55 greasy to vitreouslight to dark green, light to dark yellow to reddish brown, occasionally translucent to opaque pink. It is also but rarely found in colorless form[1]
Hydrogrossular1.7273.47 to 0.08 - 0.32vitreousgreen to bluish green, pink, white, gray
Clinozoisite1.72–1.730.01PositiveB6 to 6.53.37VitreousColorless, green, gray, light green, yellow green
Bromellite1.720–1.7350.015PositiveU93.00 to 3.02VitreousWhite, colorless
Hodgkinsonite1.720–1.7460.026NegativeB4.5 to 53.95Vitreous (Glassy)
Light pink, Orange, Reddish brown.
Synthetic spinel1.724 to 1.729I83.61 to 3.65Subadamantine To Vitreous
red, yellow, brown, light to dark green, grayish green, yellowish green, pale pink to pink, light to dark blue, greenish blue, violet, mauve, orange, colorless
Azurite1.73 –1.840.11PositiveB3.5 to 43.77 to 3.89Vitreous
Azure-blue, Berlin blue, very dark to pale blue; pale blue in transmitted light
Pyrope garne1.73 to 1.75I7.253.65 to 3.70 greasy to vitreousRed. Some varieties are very dark, almost black, while others can take tones of purple. Some chromium-rich pyropes are thermochromic, becoming green when heated
Chambersite1.732–1.7440.01PositiveB73.49VitreousColorless to deep purple
Epidote1.736–1.7700.034NegativeB6.53.25 to 3.50, usually 3.4Vitreous to resinous
Pistachio-green, yellow-green, greenish black
Pyroxmangite1.736–1.7530.017PositiveB5 to 63.76 (mean)vitreous, pearly
pink, red, brown
Musgravite1.739 to 1.7350.014 to 0.016U8 to 8.53.6 to 3.68VitreousGrey green to green
Periclase1.737I53.55 to 3.60VitreousColorless, grayish white, yellow, brownish yellow, green, black
Staurolite1.739–1.750 to 1.747–1.7620.011 to 0.015PositiveB7 to 7.53.65 to 3.78Subvitreous to resinous
Dark reddish brown to blackish brown, yellowish brown, rarely blue; pale golden yellow in thin section
Gahnospinel1.74 (mean)I83.75 (mean)VitreousGreen, Blue Dark In Tone, Very Dark Green, Brown To Black
Scorodite1.74 to 1.81Neg/PosB43.22Sub-Adamantine, Vitreous, Resinous
Green, blue-green, grey, grayish-green, blue, yellow-brown, nearly colorless, violet
Hessonite garnet1.742 to 1.748 I7.253.65VitreousBrown-red
Chrysoberyl1.75–1.76PositiveB8.53.71 to 3.72VitreousVarious shades of green, yellow, brownish to greenish black, may be raspberry-red under incandescent light when chromian; colorless, pale shades of yellow, green, or red in transmitted light
Corundum1.760-1.768 to 1.77-1.7790.008 to 0.010NegativeU93.90 to 4.00Adamantine to vitreous
Colorless, gray, brown; pink to red, orange, yellow, green, blue, violet; may be color zoned, asteriated mainly grey and brown
Almandine/ pyrope garnet1.75 to 1.78— to 0.010I7.53.80 to 3.95VitreousRed
Pyrope/almandine series garnet1.75 to 1.78I7.53.70 to 3.95 Greasy to vitreousRed. Some varieties are very dark, almost black, while others can take tones of purple. Some chromium-rich pyropes are thermochromic, becoming green when heated
Planchéite1.752 –1.81563.8SilkyBlue, greenish blue
Benitoite1.757 –1.8040.047PositiveU6.53.65 to 3.68VitreousBlue, colorless
Rhodolite1.767 to 7.53.84 to 0.001 +/-Greasy to vitreousLight to dark purplish red through reddish purple
Spinel (Ceylonite)1.77–1.80I83.63 to 3.90VitreousVarious; red to blue to mauve, dark green, brown, black
Zircon (low type) 1.78 to 1.81I63.90 to 4.10 Greasy to adamantine. Radioactive Zircon has a pitchy luster.The most common color is dark brown. Also black, gray, light brown, brownish-red, orange, pink, yellow, light blue, light green, light purple white, and colorless. Sometimes multicolored black and dark red, or multicolored with lighter and darker streaks.
reddish orange to red, slightly purplish red to reddish purple and usually dark in tone
1.78 to 1.81I7.53.95 to 4.20greasy to vitreous
reddish orange to red, slightly purplish red to reddish purple and usually dark in tone
Painite1.787 –1.8160.029NegativeU7.54.01VitreousRed, brownish, orange-red
Spessartine garnet1.79 to 1.81I7.254.12 to 4.20VitreousYellow through red
Monazite1.795– 1.8450.05Positive B65.2Resinous, vitreous to adamantine
Reddish brown, brown, pale yellow, pink, green, gray
Gahnite1.8I7.5 to 84.4VitreousDark green, bluish green, blue to indigo, yellow to brown
Cerussite1.804– 2.0780.274NegativeB3 to 3.56.46 to 6.57Adamantine, vitreous, resinous
Colorless, white, gray, blue, or green
Yttrium aluminium garnet1.838 to 8.54.57 to 4.60Adamantine, vitreous, resinous
Dark green, bluish green, blue to indigo, yellow to brown
Uvarovite garnet1.87I7.53.77VitreousGreen, emerald-green, green-black
Anglesite1.877–1.8940.017PositiveB2.75 to 36.30 to 6.39Adamantine crystals, dull when massive earthy
Colorless to white, commonly tinted gray; orange, yellow, green, blue, rarely violet
Sphene1.88– 1.990.105PositiveB5.53.52 to 3.54AdamantineYellow, brown, green, reddish
Demantoid garnet 1.89I6.53.82 to 3.85Vitreous, diamond-like, adamantine
Yellow-green, green to emerald green
Scheelite1.918–1.9340.016PositiveU4.5 to 55.9 to 6.1Vitreous to adamantine
Colorless, white, gray, brown, pale yellow, yellow-orange, pale shades of orange, red, green; may be compositionally color zoned
Yttrium oxide1.92I7.5 to 84.84vitreous to subadamantine
usually colorless, but may be pink, red, orange, yellow, green, blue, purple
‘Yttralox’1.926.55.3
Gadolinium gallium garnet1.92–2.03I6.57.05vitreous to subadamantine transparent, colorless to light brown or yellow. May also be orange or blue
Zircon (high type)1.925–1.9840.059PositiveU7 to 7.54.67 to 4.70Vitreous to adamantine; greasy when metamict.
Reddish brown, yellow, green, blue, gray, colorless; in thin section, colorless to pale brown
Rhombic yttrium aluminate1.938–1.9550.017?B85.35
Bayldonite1.95–1.990.02PositiveB4.54.35ResinousGreen, apple-green
Powellite1.974–1.9840.01PositiveU3.54.34AdamantineStraw-yellow, greenish yellow, yellow-brown, brown, colorless, may show blue to black zones
Cassiterite2.003–2.1010.098PositiveU6.56.8 to 7Adamantine to adamantine metallic, splendent; may be greasy on fractures
Black, brownish black, reddish brown, red, yellow, gray, white; rarely colorless
Zincite2.013–2.0290.016PositiveU4 to 4.55.66Subadamantine to resinous
Yellow-orange to deep red, rarely yellow, green, colorless
Boléite2.030–2.0500.02NegativeU3.55.05
Simpsonite2.060.1U76Vitreous to adamantine
White to cream, yellow to yellow-brown when altered
Euxenite2.06 to 2.266.54.7 to 5.0Brilliant submetallic, waxy to resinous on fractures
Black, brownish black,greenish black
Cubic zirconia2.09 to 2.18I8 to 8.55.98 to 6.06
Chromite2.1I5.54.1 to 4.9SubmetallicBlack to brownish black; brown to brownish black on thin edges in transmitted light
Phosgenite2.114–2.1400.026PositiveU36.2AdamantinePale yellow to yellowish brown, pale brown, smoky brown, smoky violet; colorless, pale rose, gray, yellowish gray, pale green
Mimetite2.120–2.1350.015NegativeU3.57.0 to 7.25Resinous, subadamantine
Pale to bright yellow, yellowish brown, yellow-orange, white, may be colorless
Manganot- antalite2.14–2.22 to 2.19–2.340.008 to 0.015B5.5–67.73–7.97VitreousScarlet-red to dark red.
Samarskite2.21B5 to 64.1 to 6.2Vitreous - resinous
Black, may have a brownish tint, brown to yellowish brown due to alteration; light to dark brown in transmitted light
Lithium niobate2.21–2.300.964.64
Wulfenite2.304–2.4020.098NegativeU2.75 to 36.7 to 7Adamantine, resinous
Orange-yellow, yellow, honey-yellow, reddish-orange, rarely colorless, grey, brown, olive-green and even black
Crocoite2.31–2.660.35PositiveB2.5 to 35.9 to 6.1AdamantineOrange, red, yellow
Sphalerite2.369I3.5 to 43.9 to 4.2 Adamantine, resinous, greasy
Brown, yellow, red, green, black.
Zinc blende2.368–2.371I3.5 to 44.08 to 4.10
Stibiotantalite2.39–2.460.07PositiveB5.5 to 67.46Adamantine, ResinousYellow to dark brown, reddish or greenish brown
Calcium titanate2.4B64.05
Strontium titanate2.41I65.13AdamantineUsually colorless. Rare earth or transition metals can be added to produce red, orange, yellow, brown, blue.
Diamond2.42I103.52AdamantineTypically yellow, brown, or gray to colorless. Less often blue, green, black, translucent white, pink, violet, orange, purple, and red.
Anatase2.493–2.5540.061NegativeU5.5 to 63.82 to 3.95Adamantine to splendent, metallic
Black, reddish to yellowish brown, dark blue, gray
Greenockite2.505–2.5290.024PositiveU3.54.83 to 4.90Adamantine to resinous
Honey yellow, citron yellow, orange yellow
Brookite2.583–2.7050.122PositiveB5.5 to 63.87 to 4.08SubmetallicDeep red, reddish brown, yellowish brown, brown, or black
Rutile (natural and synthetic)2.62–2.900.287Positive B6 to 6.54.2Adamantine to submetallicReddish brown, red, pale yellow, pale blue, violet, rarely grass-green; black if high in Nb–Ta
Rutile2.62–2.900.287PositiveU6 to 6.54.2Adamantine to submetallic
Reddish brown, red, pale yellow, pale blue, violet, rarely grass-green; black if high in Nb–Ta
Carborundum2.65–2.690.043PositiveU9.253.17blue-black colour, rainbow sheen
Proustite2.7 to 3.00.3NegativeU2 to 2.55.57 to 5.64AdamantineScarlet-vermilion
Cuprite2.85I3.5 to 45.85 to 6.15Adamantine, sub-metallic, earthy
Dark red to conchineal red, sometimes almost black
Hematite2.94–3.22U6.54.95 to 5.16Metallic to splendent
Metallic gray, dull to bright red
Marble2.5 to 2.6
Nevada wonderstone6 to 6.5approx. 2.5
Unakite6 to 72.85 to 3.20
Magnetop- lumbite65.5 to 5.7Sub-MetallicGrey-black
Blue pearl2.40 to 2.65
Porcelain4 approx.2.3
Bornite34.9 to 5.4Metallic if fresh, iridescent tarnish
Copper red, bronze brown, purple
Conch pearl3.5 to 42.84 to 2.89
Fine pearl2.69 to 2.73
MicroliteI5.55.5Vitreous - Resinous
Yellowish brown, Reddish brown, Greenish brown, Green, Gray.
Chalcopyrite3.5 to 44.2 approx.MetallicBrass yellow, may have iridescent purplish tarnish.
Elephant Ivory1.542.5 to 2.751.70 to 2.00
Black clam2.20 to 2.66
Domeykite3.57.2 to 7.9MetallicTin-white to steel-gray
Pinite2.52.60 to 2.85
Mollusc shell3.5 to 4approx. 2.8
Pentlandite3.5 to 45metallicYellowish bronze
Psilomelane74.35 approx.Sub-Metallic, Dull
black with gray pyrolusite bands
Breithauptite4.5 to 57.54MetallicPale copper-red, may be with violet tint
Pyrite6.54.95 to 5.10MetallicBrass yellow - often tarnished to dull brass
Marcasite6 to 6.54.85 to 4.90MetallicTin-white on fresh surface, pale bronze-yellow, darkening on exposure, iridescent tarnish
Hippopotamus walrus and narwhal1.85 to 1.98
Cultured pearl2.70 to 2.78
NiccoliteU5 to 5.57.33 to 7.67metallicPale copper red with blackish tarnish. white with strong yellowish pink hue on polished section strongly anisotropic
CalciumB64.05
Australian pearl2.67 to 2.78
CobaltiteI5.56.0 to 6.3MetallicReddish silver white, violet steel gray to black
Algodonite3.58.38Metallic
Gray, silver white, steel gray, tarnishes dull bronze
KakortokiteVaries2.7 to 2.8
Barium titanate2.406 to 6.55.9
gemstone identification chart

gemstone identification chart