Rock Identifier

Category

Organic Gemstone

Browse organic gemstone specimens identified by the Rock Identifier community.

Learn about Organic Gemstone in the encyclopedia

Jet

Jet

Sapropel

Sapropel

Red Garnet

Red Garnet

Bituminous Shale

Bituminous Shale

Black Shale

Black Shale

Petrified Wood

Petrified Wood

Amber

Amber

Peat

Peat

Oil Shale

Oil Shale

Pearl

Pearl

Lizard Skin Jasper

Lizard Skin Jasper

Rhodonite

Rhodonite

Olivine in Basalt (Peridotite / Forsterite ((Mg,Fe)2SiO4)) — igneous

Olivine in Basalt

Peridotite / Forsterite ((Mg,Fe)2SiO4)

Opal (Hydrated amorphous silica (SiO2·nH2O)) — mineral

Opal

Hydrated amorphous silica (SiO2·nH2O)

Quartz (Silicon Dioxide (SiO2)) — mineral

Quartz

Silicon Dioxide (SiO2)

Prehnite (Prehnite (Ca2Al(AlSi3O10)(OH)2)) — mineral

Prehnite

Prehnite (Ca2Al(AlSi3O10)(OH)2)

Quartz Crystal Fragment (Silicon Dioxide (SiO2)) — mineral

Quartz Crystal Fragment

Silicon Dioxide (SiO2)

Quartz (Milky Quartz) (Silicon Dioxide (SiO2)) — mineral

Quartz (Milky Quartz)

Silicon Dioxide (SiO2)

Amazonite (Potassium Aluminum Silicate (KAlSi3O8)) — mineral

Amazonite

Potassium Aluminum Silicate (KAlSi3O8)

Chalcedony (Botryoidal/Tumbled Agate) (Silicon Dioxide (SiO2)) — mineral

Chalcedony (Botryoidal/Tumbled Agate)

Silicon Dioxide (SiO2)

Blue Tiger's Eye (Hawks Eye) (Pseudomorph of Quartz after Crocidolite (SiO2)) — metamorphic

Blue Tiger's Eye (Hawks Eye)

Pseudomorph of Quartz after Crocidolite (SiO2)

Moonstone (Rainbow Moonstone) (Labradorite (White Labradorite) - (Na,Ca)(Al,Si)4O8) — mineral

Moonstone (Rainbow Moonstone)

Labradorite (White Labradorite) - (Na,Ca)(Al,Si)4O8

Amazonite (Microcline (KAlSi3O8) with trace lead (Pb)) — mineral

Amazonite

Microcline (KAlSi3O8) with trace lead (Pb)

Prehnite (Prehnite, Ca2Al2Si3O10(OH)2) — mineral

Prehnite

Prehnite, Ca2Al2Si3O10(OH)2

Quartz Crystal Fragment (Silicon Dioxide (SiO2)) — mineral

Quartz Crystal Fragment

Silicon Dioxide (SiO2)

Blue Chalcedony (Silicon Dioxide (SiO2)) — mineral

Blue Chalcedony

Silicon Dioxide (SiO2)

Moonstone (specifically Rainbow Moonstone / White Labradorite) (White Labradorite (Feldspar Group: (Na,Ca)(Al,Si)4O8)) — mineral

Moonstone (specifically Rainbow Moonstone / White Labradorite)

White Labradorite (Feldspar Group: (Na,Ca)(Al,Si)4O8)

Ametrine (Ametrine (SiO2 - Silicon Dioxide with varied iron impurities)) — mineral

Ametrine

Ametrine (SiO2 - Silicon Dioxide with varied iron impurities)

Agate Geode Slice (with Druzy Quartz) (Silicon Dioxide (SiO2)) — mineral

Agate Geode Slice (with Druzy Quartz)

Silicon Dioxide (SiO2)

Quartz (Silicon dioxide (SiO2)) — Mineral

Quartz

Silicon dioxide (SiO2)

Indochinite Tektite (Tektite (high-silica impact glass)) — igneous

Indochinite Tektite

Tektite (high-silica impact glass)

Chert (White/Light Tan) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (White/Light Tan)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Limonite-stained Chert (Microcrystalline Quartz (SiO2) with Hydrated Iron Oxides (FeO(OH)·nH2O)) — sedimentary

Limonite-stained Chert

Microcrystalline Quartz (SiO2) with Hydrated Iron Oxides (FeO(OH)·nH2O)

Petrified Wood (Agatized/Silicified Wood) (Silicified Wood (SiO2)) — metamorphic

Petrified Wood (Agatized/Silicified Wood)

Silicified Wood (SiO2)

Petrified Wood (Silicified Wood (SiO2)) — metamorphic

Petrified Wood

Silicified Wood (SiO2)

Petrified Wood (Silicified wood (Quartz/Chalcedony - SiO2)) — sedimentary

Petrified Wood

Silicified wood (Quartz/Chalcedony - SiO2)

Petrified Wood (Silicified Wood (SiO2)) — sedimentary

Petrified Wood

Silicified Wood (SiO2)

Chert Pebble with Quartz Veins (Microcrystalline Quartz (SiO2)) — sedimentary

Chert Pebble with Quartz Veins

Microcrystalline Quartz (SiO2)

Septarian Nodule (Septarian Concretion) — sedimentary

Septarian Nodule

Septarian Concretion

Chert (specifically Tan/Brown Chert) (Chert (SiO2)) — sedimentary

Chert (specifically Tan/Brown Chert)

Chert (SiO2)

Rough Tanzanite (Zoisite (Ca2Al3(SiO4)3(OH))) — mineral

Rough Tanzanite

Zoisite (Ca2Al3(SiO4)3(OH))

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

Sunstone

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

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

Amethyst

Silicon Dioxide with trace Iron (SiO2)

Amazonite (K(AlSi3O8)) — mineral

Amazonite

K(AlSi3O8)

Rhodonite (Manganese Silicate (Mn,Fe,Mg,Ca)SiO3) — mineral

Rhodonite

Manganese Silicate (Mn,Fe,Mg,Ca)SiO3

Red Garnet (Pyrope or Almandine (X3Y2(SiO4)3)) — mineral

Red Garnet

Pyrope or Almandine (X3Y2(SiO4)3)

Moldavite (Moldavite (Siliceous vitreous substance)) — tektite (natural glass)

Moldavite

Moldavite (Siliceous vitreous substance)

tektite (natural glass)

Moonstone (Orthoclase Feldspar) ((K,Na)AlSi3O8) — mineral

Moonstone (Orthoclase Feldspar)

(K,Na)AlSi3O8

Aquamarine (Beryl (Be3Al2Si6O18)) — mineral

Aquamarine

Beryl (Be3Al2Si6O18)

Citrine (Quartz (SiO₂) variety) — Mineral

Citrine

Quartz (SiO₂) variety

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

Emerald

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

Citrine (Silicon Dioxide (SiO2) - Macrocrystalline Quartz variety) — mineral

Citrine

Silicon Dioxide (SiO2) - Macrocrystalline Quartz variety

Red Jasper (Silicon Dioxide (SiO2) with Iron inclusions) — sedimentary

Red Jasper

Silicon Dioxide (SiO2) with Iron inclusions

Rhodonite (Manganese Silicate (MnSiO₃)) — mineral

Rhodonite

Manganese Silicate (MnSiO₃)