Rock Identifier

Category

Mineral And Organic Gemstone

Browse mineral and organic gemstone specimens identified by the Rock Identifier community.

Sandstone (likely Fossilized Wood or Concrete Simulacrum) (Arenite / Silicified Wood / Anthropogenic Concrete) — sedimentary

Sandstone (likely Fossilized Wood or Concrete Simulacrum)

Arenite / Silicified Wood / Anthropogenic Concrete

Petrified Wood (Silicified Wood (SiO2)) — sedimentary

Petrified Wood

Silicified Wood (SiO2)

Pyrite on Limestone (Iron Disulfide (FeS2) in Calcium Carbonate (CaCO3) matrix) — sedimentary (matrix) / mineral (inclusion)

Pyrite on Limestone

Iron Disulfide (FeS2) in Calcium Carbonate (CaCO3) matrix

sedimentary (matrix) / mineral (inclusion)

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

Prehnite

Prehnite (Ca2Al2Si3O10(OH)2)

Petrified Wood (Silicified Wood (SiO2)) — sedimentary

Petrified Wood

Silicified Wood (SiO2)

Orthoceras Fossil in Limestone (Orthoceras (extinct genus of cephalopods) in Carboniferous or Devonian Limestone) — sedimentary

Orthoceras Fossil in Limestone

Orthoceras (extinct genus of cephalopods) in Carboniferous or Devonian Limestone

Chert (Jasper/Limonitic Chert) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (Jasper/Limonitic Chert)

Microcrystalline Quartz (SiO2)

Petrified Wood (Silicified Wood (SiO2)) — sedimentary

Petrified Wood

Silicified Wood (SiO2)

Ferruginous Chert (Microcrystalline Quartz (SiO2) with Iron Oxides) — sedimentary

Ferruginous Chert

Microcrystalline Quartz (SiO2) with Iron Oxides

Fossilized Crinoid Stem Segment (Crinoid (Phylum Echinodermata, Class Crinoidea)) — sedimentary

Fossilized Crinoid Stem Segment

Crinoid (Phylum Echinodermata, Class Crinoidea)

Moss Agate (Chalcedony (Silicon Dioxide with inclusions) - SiO2) — mineral

Moss Agate

Chalcedony (Silicon Dioxide with inclusions) - SiO2

Moss Agate (Chalcedony (SiO2) with inclusions of manganese or iron oxides) — mineral

Moss Agate

Chalcedony (SiO2) with inclusions of manganese or iron oxides

Green Moss Agate (Agate (Silicon Dioxide - SiO2 with inclusions of Manganese/Iron oxides)) — mineral

Green Moss Agate

Agate (Silicon Dioxide - SiO2 with inclusions of Manganese/Iron oxides)

Chert (specifically Flint or Jasper variant) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (specifically Flint or Jasper variant)

Microcrystalline Quartz (SiO2)

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

Petrified Wood

Silicified Wood (primarily SiO2)

Fossilized Shark Tooth (Scapanorhynchus (Sand Tiger Shark relative)) — sedimentary

Fossilized Shark Tooth

Scapanorhynchus (Sand Tiger Shark relative)

Chert (often called Flint or Jasper) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (often called Flint or Jasper)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Shale (Shale (comprised mostly of clay minerals and quartz)) — sedimentary

Shale

Shale (comprised mostly of clay minerals and quartz)

Pyrite Geode (Sparkling Druzy) (Iron Sulfide (FeS2) in Sedimentary Nodule) — mineral

Pyrite Geode (Sparkling Druzy)

Iron Sulfide (FeS2) in Sedimentary Nodule

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

Tiger's Eye

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

Pyrite in Shale (Iron Sulfide (FeS2) in Sedimentary Matrix) — mineral

Pyrite in Shale

Iron Sulfide (FeS2) in Sedimentary Matrix

Pyrite (Fool's Gold) (Iron Disulfide (FeS2)) — mineral

Pyrite (Fool's Gold)

Iron Disulfide (FeS2)

Mother of Pearl (Nacre) (Nacre (Aragonite/Conchiolin), CaCO3 + Organic Polymers) — mineral

Mother of Pearl (Nacre)

Nacre (Aragonite/Conchiolin), CaCO3 + Organic Polymers

Pyrite (Iron Disulfide (FeS2)) — mineral

Pyrite

Iron Disulfide (FeS2)

Feldspar (KAlSi3O8 - NaAlSi3O8 - CaAl2Si2O8) — mineral

Feldspar

KAlSi3O8 - NaAlSi3O8 - CaAl2Si2O8

Chert (containing Iron Oxide) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (containing Iron Oxide)

Microcrystalline Quartz (SiO2)

Chert (Flint) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (Flint)

Microcrystalline Quartz (SiO2)

Chert (with Limestone matrix) (Silicon dioxide (SiO2)) — sedimentary

Chert (with Limestone matrix)

Silicon dioxide (SiO2)

Amazonite (Potassium aluminum silicate (KAlSi3O8)) — mineral

Amazonite

Potassium aluminum silicate (KAlSi3O8)

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

Rough Citrine Quartz

Silicon Dioxide (SiO2) with iron impurities

Emerald (Faceted Gemstone) (Beryl (Be3Al2Si6O18 with Chromium/Vanadium impurities)) — mineral

Emerald (Faceted Gemstone)

Beryl (Be3Al2Si6O18 with Chromium/Vanadium impurities)

Botryoidal Chalcedony (Silicon Dioxide (SiO2)) — mineral

Botryoidal Chalcedony

Silicon Dioxide (SiO2)

Opal (Hydrated Amorphous Silica (SiO2·nH2O)) — mineral

Opal

Hydrated Amorphous Silica (SiO2·nH2O)

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

Quartz (Smoky Quartz variant)

Silicon Dioxide (SiO2)

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

Amethyst (Quartz variety)

Silicon Dioxide (SiO2) with iron impurities

Pearl (Calcium Carbonate (Aragonite or Calcite) and Conchiolin) — Mineraloid

Pearl

Calcium Carbonate (Aragonite or Calcite) and Conchiolin

Alexandrite (Chrysoberyl (BeAl2O4 with Chromium impurities)) — mineral

Alexandrite

Chrysoberyl (BeAl2O4 with Chromium impurities)

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

Quartz (Clear Quartz/Rock Crystal)

Silicon Dioxide (SiO2)

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

Emerald

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

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

Almandine Garnet in Matrix

Almandine, Fe3Al2(SiO4)3

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

Amethyst (Raw Quartz)

Silicon Dioxide (SiO2) with iron impurities

Carnelian (Chalcedony) (Silicon Dioxide (SiO2)) — mineral

Carnelian (Chalcedony)

Silicon Dioxide (SiO2)