Rock Identifier

Category

Organic Gemstone (Not A Mineral)

Browse organic gemstone (not a mineral) specimens identified by the Rock Identifier community.

Learn about Organic Gemstone (Not A Mineral) in the encyclopedia

Black Shale

Black Shale

Jet

Jet

Malachite

Malachite

Sapropel

Sapropel

Bituminous Shale

Bituminous Shale

Red Garnet

Red Garnet

Shungite

Shungite

Anatase

Anatase

Sperrylite

Sperrylite

Amber

Amber

Hutcheonite

Hutcheonite

Coal

Coal

Amazonite (Amazonite (KAlSi3O8); a green variety of Microcline feldspar) — mineral

Amazonite

Amazonite (KAlSi3O8); a green variety of Microcline feldspar

Amethyst (SiO2 (Silicon Dioxide) with Iron (Fe3+) impurities) — mineral

Amethyst

SiO2 (Silicon Dioxide) with Iron (Fe3+) impurities

Rough Citrine Quartz (Citrine (Silicon Dioxide, SiO2 with iron impurities)) — mineral

Rough Citrine Quartz

Citrine (Silicon Dioxide, SiO2 with iron impurities)

Smoky Quartz (Smoky Quartz (Silicon Dioxide - SiO2)) — mineral

Smoky Quartz

Smoky Quartz (Silicon Dioxide - SiO2)

Blue Tiger's Eye (Pseudomorph of Quartz after Crocidolite (SiO2 with inclusions of asbestiform silicates)) — mineral

Blue Tiger's Eye

Pseudomorph of Quartz after Crocidolite (SiO2 with inclusions of asbestiform silicates)

Sunstone (Aventurine Feldspar (Plagioclase Feldspar with inclusions)) — mineral

Sunstone

Aventurine Feldspar (Plagioclase Feldspar with inclusions)

Red Beryl (Bixbite (Be3Al2Si6O18 with Mn3+ ions)) — mineral

Red Beryl

Bixbite (Be3Al2Si6O18 with Mn3+ ions)

Peridot (Olivine) (Magnesium Iron Silicate (Mg,Fe)2SiO4) — mineral

Peridot (Olivine)

Magnesium Iron Silicate (Mg,Fe)2SiO4

Moonstone (Tumbled) (Potassium Aluminum Silicate (KAlSi3O8) with inclusions of Albite) — mineral

Moonstone (Tumbled)

Potassium Aluminum Silicate (KAlSi3O8) with inclusions of Albite

Chert (Yellow Jasper/Flint) (Silicon Dioxide (SiO2) - Microcrystalline Quartz) — sedimentary

Chert (Yellow Jasper/Flint)

Silicon Dioxide (SiO2) - Microcrystalline Quartz

Chert (often called Flint in this context) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (often called Flint in this context)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Quartz (Chatoyant or Milky variety) (Silicon Dioxide (SiO2)) — mineral

Quartz (Chatoyant or Milky variety)

Silicon Dioxide (SiO2)

Jasper (Green/Yellow Moss Jasper) (Silicon Dioxide (SiO2)) — mineral

Jasper (Green/Yellow Moss Jasper)

Silicon Dioxide (SiO2)

Chert (often called Flint when in chalk or limestone) (Silicon Dioxide (SiO₂)) — sedimentary

Chert (often called Flint when in chalk or limestone)

Silicon Dioxide (SiO₂)

Chert (Flinty variety) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (Flinty variety)

Microcrystalline Quartz (SiO2)

Aquamarine (Beryl (Be₃Al₂Si‑₆O₁‑₈)) — mineral

Aquamarine

Beryl (Be₃Al₂Si‑₆O₁‑₈)

Rose Quartz (Silicon Dioxide (SiO2) with trace amounts of titanium, iron, or manganese) — mineral

Rose Quartz

Silicon Dioxide (SiO2) with trace amounts of titanium, iron, or manganese

Citrine Quartz (Silicon Dioxide (SiO2)) — mineral

Citrine Quartz

Silicon Dioxide (SiO2)

Citrine Quartz (Crystalline Quartz (SiO2) with iron impurities) — mineral

Citrine Quartz

Crystalline Quartz (SiO2) with iron impurities

Amazonite (Microcline (KAlSi3O8 variant)) — mineral

Amazonite

Microcline (KAlSi3O8 variant)

Amethyst (Amethyst (Purple Quartz); formula: SiO2 (Silicon Dioxide)) — mineral

Amethyst

Amethyst (Purple Quartz); formula: SiO2 (Silicon Dioxide)

Emerald (Beryl (Be3Al2(SiO3)6) with trace Chromium/Vanadium) — mineral

Emerald

Beryl (Be3Al2(SiO3)6) with trace Chromium/Vanadium

Quartz (Clear Quartz/Rock Crystal) (Silicon Dioxide (SiO2)) — mineral

Quartz (Clear Quartz/Rock Crystal)

Silicon Dioxide (SiO2)

Sugilite (KNa2(Fe,Mn,Al)2Li3Si12O30 (Potassium Sodium Lithium Iron Manganese Aluminum Silicate)) — mineral

Sugilite

KNa2(Fe,Mn,Al)2Li3Si12O30 (Potassium Sodium Lithium Iron Manganese Aluminum Silicate)

Amethyst (Silicon Dioxide (SiO2) with iron impurities) — Mineral

Amethyst

Silicon Dioxide (SiO2) with iron impurities

Amethyst (Silicon Dioxide (SiO2) with iron impurities) — mineral

Amethyst

Silicon Dioxide (SiO2) with iron impurities

Bloodstone (Heliotrope) (Cryptocrystalline Quartz (SiO2) with inclusions of Hematite or Chlorite) — mineral

Bloodstone (Heliotrope)

Cryptocrystalline Quartz (SiO2) with inclusions of Hematite or Chlorite

Amethyst (Amethyst (Silicon Dioxide, SiO2)) — mineral

Amethyst

Amethyst (Silicon Dioxide, SiO2)

Amethyst (Silicon Dioxide (SiO2) with Fe3+ impurities) — mineral

Amethyst

Silicon Dioxide (SiO2) with Fe3+ impurities

Amethyst (Amethyst (SiO2 with iron impurities)) — mineral

Amethyst

Amethyst (SiO2 with iron impurities)

Sunstone (Plagioclase Feldspar (Na,Ca)(Si,Al)4O8) — mineral

Sunstone

Plagioclase Feldspar (Na,Ca)(Si,Al)4O8

Smoky Quartz (Silicon Dioxide (SiO2)) — mineral

Smoky Quartz

Silicon Dioxide (SiO2)

Citrine (Citrine (Silicon Dioxide, SiO2)) — mineral

Citrine

Citrine (Silicon Dioxide, SiO2)

Amethyst (SiO2 (Silicon Dioxide with Iron impurities)) — mineral

Amethyst

SiO2 (Silicon Dioxide with Iron impurities)

Beryl (Emerald or Aquamarine in Matrix) (Beryllium Aluminum Silicate (Be3Al2Si6O18)) — mineral

Beryl (Emerald or Aquamarine in Matrix)

Beryllium Aluminum Silicate (Be3Al2Si6O18)

Sunstone (Aventurine Feldspar (composition: (Ca,Na)((Al,Si)2Si2O8))) — mineral

Sunstone

Aventurine Feldspar (composition: (Ca,Na)((Al,Si)2Si2O8))

Aquamarine (Beryl) (Beryllium aluminum silicate (Be3Al2Si6O18)) — mineral

Aquamarine (Beryl)

Beryllium aluminum silicate (Be3Al2Si6O18)

Amethyst (Silicon Dioxide (SiO2) with Iron impurities) — mineral

Amethyst

Silicon Dioxide (SiO2) with Iron impurities

Chlorastrolite (Greenstone) (Chlorastrolite (Pumpellyite variety), Ca2(Mg,Fe)Al2(SiO4)(Si2O7)(OH)2·H2O) — mineral

Chlorastrolite (Greenstone)

Chlorastrolite (Pumpellyite variety), Ca2(Mg,Fe)Al2(SiO4)(Si2O7)(OH)2·H2O

Peridot (Olivine ((Mg, Fe)2SiO4)) — mineral

Peridot

Olivine ((Mg, Fe)2SiO4)

Smoky Quartz (Silicon Dioxide (SiO2)) — mineral

Smoky Quartz

Silicon Dioxide (SiO2)

Sunstone (Orthoclase or Oligoclase Feldspar (Na,Ca)(Al,Si)4O8) — mineral

Sunstone

Orthoclase or Oligoclase Feldspar (Na,Ca)(Al,Si)4O8