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

Blue Quartz (specifically Dumortierite Quartz) (Silicon Dioxide (SiO2) with inclusions of Dumortierite (Al7BO3(SiO4)3O3)) — metamorphic

Blue Quartz (specifically Dumortierite Quartz)

Silicon Dioxide (SiO2) with inclusions of Dumortierite (Al7BO3(SiO4)3O3)

Green Fluorite (Fluorite (Calcium Fluoride, CaF2)) — mineral

Green Fluorite

Fluorite (Calcium Fluoride, CaF2)

Tiger's Eye (SiO2 (Silicon Dioxide with Iron Oxide inclusions)) — Mineral (Metamorphic pseudomorph)

Tiger's Eye

SiO2 (Silicon Dioxide with Iron Oxide inclusions)

Mineral (Metamorphic pseudomorph)

Tiger's Eye (Pseudomorph of Quartz after Crocidolite (SiO2 with iron oxide inclusions)) — metamorphic

Tiger's Eye

Pseudomorph of Quartz after Crocidolite (SiO2 with iron oxide inclusions)

Milky Quartz (Silicon Dioxide (SiO2)) — mineral

Milky Quartz

Silicon Dioxide (SiO2)

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

Amethyst (in jewelry)

Silicon Dioxide (SiO2) with iron impurities

Rutilated Quartz (Silicon Dioxide (SiO2) with Titanium Dioxide (TiO2) inclusions) — mineral

Rutilated Quartz

Silicon Dioxide (SiO2) with Titanium Dioxide (TiO2) inclusions

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

Amethyst Geode

Amethyst (Silicon Dioxide, SiO2)

Almandine Garnet (Almandine (Fe3Al2(SiO4)3)) — mineral

Almandine Garnet

Almandine (Fe3Al2(SiO4)3)

Moonstone (Adularia (orthoclase) or Albite (plagioclase), a feldspar mineral (KAlSi3O8 or NaAlSi3O8 respectively, often a mixture)) — mineral

Moonstone

Adularia (orthoclase) or Albite (plagioclase), a feldspar mineral (KAlSi3O8 or NaAlSi3O8 respectively, often a mixture)

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

Amethyst Quartz (Amethyst Geode)

Silicon Dioxide (SiO2) with iron impurities

Rose Quartz (Quartz (SiO₂), variety Rose Quartz) — Mineral

Rose Quartz

Quartz (SiO₂), variety Rose Quartz

Common Opal with Host Rock (Opal (Hydrated silica, SiO2·nH2O)) — mineral

Common Opal with Host Rock

Opal (Hydrated silica, SiO2·nH2O)

Amazonite (Amazonite (KAlSi3O8)) — mineral

Amazonite

Amazonite (KAlSi3O8)

Turquoise (CuAl6(PO4)4(OH)8·4H2O (Hydrous Phosphate of Copper and Aluminum)) — mineral

Turquoise

CuAl6(PO4)4(OH)8·4H2O (Hydrous Phosphate of Copper and Aluminum)

Green Fluorite (Fluorite (Calcium Fluoride, CaF2)) — mineral

Green Fluorite

Fluorite (Calcium Fluoride, CaF2)

Quartz with Mica/Host Rock (Silicon Dioxide (SiO2) with Phyllosilicates) — mineral

Quartz with Mica/Host Rock

Silicon Dioxide (SiO2) with Phyllosilicates

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

Quartz (Common or Milky)

Silicon Dioxide (SiO2)

Milky Quartz (Silicon Dioxide (SiO2)) — mineral

Milky Quartz

Silicon Dioxide (SiO2)

Iron-stained Quartz (Silicon Dioxide (SiO2) with Hematite/Limonite impurities) — mineral

Iron-stained Quartz

Silicon Dioxide (SiO2) with Hematite/Limonite impurities

Quartz (Variety: Citrine or Tumbled Chalcedony) (Silicon Dioxide (SiO2)) — mineral

Quartz (Variety: Citrine or Tumbled Chalcedony)

Silicon Dioxide (SiO2)

Milky Quartz (Silicon Dioxide (SiO2)) — mineral

Milky Quartz

Silicon Dioxide (SiO2)

Yellow Quartz (Citrinated Quartz) (Silicon Dioxide (SiO2)) — mineral

Yellow Quartz (Citrinated Quartz)

Silicon Dioxide (SiO2)

Herkimer Diamond (Quartz (Silicon Dioxide) - SiO2) — mineral

Herkimer Diamond

Quartz (Silicon Dioxide) - SiO2

Green Jasper (Silicon Dioxide (SiO2) with iron silicate inclusions) — sedimentary

Green Jasper

Silicon Dioxide (SiO2) with iron silicate inclusions

Blue Quartzite (Quartzite (primarily SiO2) with inclusions like Dumortierite or Crocidolite) — metamorphic

Blue Quartzite

Quartzite (primarily SiO2) with inclusions like Dumortierite or Crocidolite

Aventurine Quartz (Silicon Dioxide (SiO2) with Fuchsite inclusions) — gemstone

Aventurine Quartz

Silicon Dioxide (SiO2) with Fuchsite inclusions

Pegmatite (Coarse-grained Igneous Rock (Granitic Pegmatite)) — igneous

Pegmatite

Coarse-grained Igneous Rock (Granitic Pegmatite)

Yellow Quartz (Citrine/Yellow Jasper mix) (Silicon Dioxide (SiO2)) — mineral

Yellow Quartz (Citrine/Yellow Jasper mix)

Silicon Dioxide (SiO2)

Prasiolite and Quartz Crystal Cluster (Quartz (SiO2); Prasiolite is a variety of Quartz) — mineral

Prasiolite and Quartz Crystal Cluster

Quartz (SiO2); Prasiolite is a variety of Quartz

Quartz Pebble (Silicon Dioxide (SiO2)) — mineral

Quartz Pebble

Silicon Dioxide (SiO2)

Quartz (Microcrystalline/Gravel) (Silicon Dioxide (SiO2)) — mineral

Quartz (Microcrystalline/Gravel)

Silicon Dioxide (SiO2)

Shale or Mudstone (Based on appearance) (Shale (fine-grained, laminated fissile sedimentary rock) / Mudstone (fine-grained, non-fissile sedimentary rock)) — Sedimentary

Shale or Mudstone (Based on appearance)

Shale (fine-grained, laminated fissile sedimentary rock) / Mudstone (fine-grained, non-fissile sedimentary rock)

Jasper (Silicon Dioxide (SiO2)) — sedimentary/mineral

Jasper

Silicon Dioxide (SiO2)

sedimentary/mineral

Pegmatite (Granitic) (Granite Pegmatite) — igneous

Pegmatite (Granitic)

Granite Pegmatite

Pegmatite (Granitic Pegmatite) — igneous

Pegmatite

Granitic Pegmatite

Granitic Pegmatite (Granite Pegmatite (coarse-grained intrusive igneous rock)) — igneous

Granitic Pegmatite

Granite Pegmatite (coarse-grained intrusive igneous rock)

Fossilized Wood (Petrified Wood) (Silicified Wood (primarily quartz/chalcedony replacing organic matter)) — Sedimentary (with some aspects of mineral replacement)

Fossilized Wood (Petrified Wood)

Silicified Wood (primarily quartz/chalcedony replacing organic matter)

Sedimentary (with some aspects of mineral replacement)

Dalmatian Stone (commonly Dyed) (Dalmatian Jasper (Peralkaline igneous rock)) — igneous

Dalmatian Stone (commonly Dyed)

Dalmatian Jasper (Peralkaline igneous rock)

Fuchsite (Green Muscovite in Quartz) (Chromium-rich Muscovite (K(Al,Cr)2(AlSi3O10)(OH)2)) — metamorphic

Fuchsite (Green Muscovite in Quartz)

Chromium-rich Muscovite (K(Al,Cr)2(AlSi3O10)(OH)2)

Obsidian (Volcanic Glass (predominantly SiO2)) — igneous

Obsidian

Volcanic Glass (predominantly SiO2)

Hematite (Iron(III) oxide (Fe2O3)) — mineral

Hematite

Iron(III) oxide (Fe2O3)