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

Citrine (Silicon Dioxide (SiO2)) — mineral

Citrine

Silicon Dioxide (SiO2)

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

Moonstone

Orthoclase Feldspar (formula: (K,Na)AlSi3O8)

Chert Pebble (Chert (Microcrystalline Quartz, SiO2)) — sedimentary

Chert Pebble

Chert (Microcrystalline Quartz, SiO2)

Sphalerite in Matrix (Polished Point) (Zinc sulfide (Zn,Fe)S) — mineral

Sphalerite in Matrix (Polished Point)

Zinc sulfide (Zn,Fe)S

Ironstone Concretion (Limonite/Goethite) (Iron oxide concretion (contains FeO(OH)·nH2O)) — sedimentary

Ironstone Concretion (Limonite/Goethite)

Iron oxide concretion (contains FeO(OH)·nH2O)

Brachiopod Fossil in Limestone (Phylum Brachiopoda (likely Order Spiriferida), CaCO3 (Calcite)) — sedimentary

Brachiopod Fossil in Limestone

Phylum Brachiopoda (likely Order Spiriferida), CaCO3 (Calcite)

Raw Corundum (Sapphire/Ruby variant) (Aluminum oxide (Al2O3)) — mineral

Raw Corundum (Sapphire/Ruby variant)

Aluminum oxide (Al2O3)

Chrysocolla (with Quartz and Azurite) (Hydrated copper phyllosilicate mineral [Cu2-xAlx(H2-xSi2O5)(OH)4·n(H2O)]) — mineral

Chrysocolla (with Quartz and Azurite)

Hydrated copper phyllosilicate mineral [Cu2-xAlx(H2-xSi2O5)(OH)4·n(H2O)]

Magnetite (in matrix) (Magnetite (Fe3O4)) — mineral

Magnetite (in matrix)

Magnetite (Fe3O4)

Potassium Feldspar (Orthoclase) (Orthoclase (KAlSi3O8)) — mineral

Potassium Feldspar (Orthoclase)

Orthoclase (KAlSi3O8)

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

Quartz (Clear Quartz)

Silicon Dioxide (SiO2)

Fluorite (Calcium Fluoride (CaF2)) — mineral

Fluorite

Calcium Fluoride (CaF2)

Yellow Chert (Yellow Jasper) (Silicon dioxide (SiO2)) — sedimentary

Yellow Chert (Yellow Jasper)

Silicon dioxide (SiO2)

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

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Petrified Wood (Silicified Wood (SiO2)) — Mineral / Fossil

Petrified Wood

Silicified Wood (SiO2)

Mineral / Fossil

Orthoclase Feldspar with Quartz (Orthoclase (KAlSi3O8)) — mineral

Orthoclase Feldspar with Quartz

Orthoclase (KAlSi3O8)

Garnet in Matrix (Almandine Garnet (Fe3Al2(SiO4)3)) — metamorphic

Garnet in Matrix

Almandine Garnet (Fe3Al2(SiO4)3)

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

Moonstone

Orthoclase Feldspar ((K,Na)AlSi3O8)

Tiger's Eye (Tiger's eye (Pseudomorph of Quartz after Crocidolite), SiO2) — metamorphic

Tiger's Eye

Tiger's eye (Pseudomorph of Quartz after Crocidolite), SiO2

Black Opal (Hydrated Amorphous Silica (SiO2·nH2O)) — Mineral

Black Opal

Hydrated Amorphous Silica (SiO2·nH2O)

Quartz (Silicon dioxide (SiO2)) — mineral

Quartz

Silicon dioxide (SiO2)

Septarian Nodule (Septarian Concretion (CaCO3 with Siderite/Calcite/Aragonite)) — sedimentary

Septarian Nodule

Septarian Concretion (CaCO3 with Siderite/Calcite/Aragonite)

Jasper (Jasper (Silicon Dioxide, SiO2)) — sedimentary

Jasper

Jasper (Silicon Dioxide, SiO2)

Banded Chert (Microcrystalline Quartz (SiO2)) — sedimentary

Banded Chert

Microcrystalline Quartz (SiO2)

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

Fluorite

Fluorite (Calcium Fluoride, CaF2)

Chert (Jasper) (Sedimentary Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (Jasper)

Sedimentary Cryptocrystalline Quartz (SiO2)

Chert (Nodule) (Silicon Dioxide (SiO2)) — sedimentary

Chert (Nodule)

Silicon Dioxide (SiO2)

Red Jasper (Silicon Dioxide (SiO2) with Hematite impurities) — sedimentary

Red Jasper

Silicon Dioxide (SiO2) with Hematite impurities

Coral Fossil (Petrified Coral) (Scleractinia (Order) - Calcified Fossil Skeleton (CaCO3)) — sedimentary

Coral Fossil (Petrified Coral)

Scleractinia (Order) - Calcified Fossil Skeleton (CaCO3)

Petrified Wood (Silicified Wood (primarily SiO2)) — sedimentary

Petrified Wood

Silicified Wood (primarily SiO2)

Ironstone Concretion / Hematite Nodules (Ferruginous Sedimentary Rock (primarily Hematite Fe2O3 and Goethite FeO(OH))) — sedimentary

Ironstone Concretion / Hematite Nodules

Ferruginous Sedimentary Rock (primarily Hematite Fe2O3 and Goethite FeO(OH))

Travertine (often colloquially called Tufa) (Chemical Sedimentary Calcium Carbonate (CaCO3)) — sedimentary

Travertine (often colloquially called Tufa)

Chemical Sedimentary Calcium Carbonate (CaCO3)

Petrified Wood (Silicified Wood (primarily Quartz / Chalcedony: SiO2)) — metamorphic

Petrified Wood

Silicified Wood (primarily Quartz / Chalcedony: SiO2)

Chert (Chalcedony/Agate) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (Chalcedony/Agate)

Microcrystalline Quartz (SiO2)

Aquamarine (Beryl (Be3Al2Si6O18 with iron impurities)) — gemstone

Aquamarine

Beryl (Be3Al2Si6O18 with iron impurities)

Jasper (Agate/Jasper (Microcrystalline Quartz, SiO2)) — sedimentary

Jasper

Agate/Jasper (Microcrystalline Quartz, SiO2)

Septarian Nodule (Dragon Stone) (Septarian Concretion (CaCO3 with Siderite and Calcite)) — sedimentary

Septarian Nodule (Dragon Stone)

Septarian Concretion (CaCO3 with Siderite and Calcite)

Septarian Nodule (Dragon Stone) (Septarian Geode (CaCO3 + Mg + Fe)) — sedimentary

Septarian Nodule (Dragon Stone)

Septarian Geode (CaCO3 + Mg + Fe)

Petrified Wood (Silicified Wood (SiO2)) — sedimentary

Petrified Wood

Silicified Wood (SiO2)

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

Petrified Wood

Silicified wood (Quartz/Chalcedony/SiO2)

Petrified Rugose Coral (Horn Coral) (Order Rugosa (extinct coral)) — sedimentary

Petrified Rugose Coral (Horn Coral)

Order Rugosa (extinct coral)

Chrysocolla (Chrysocolla (Cu2-xAlx(H2-xSi2O5)(OH)4·nH2O)) — mineral

Chrysocolla

Chrysocolla (Cu2-xAlx(H2-xSi2O5)(OH)4·nH2O)