Rock Identifier

Category

Organic Gemstone (Sedimentary Classification)

Browse organic gemstone (sedimentary classification) specimens identified by the Rock Identifier community.

Blue Chalcedony (Chalcedony (a cryptocrystalline variety of Quartz - SiO₂)) — Mineral

Blue Chalcedony

Chalcedony (a cryptocrystalline variety of Quartz - SiO₂)

Moss Agate (Silicon Dioxide with inclusions (SiO2 + Mn/Fe oxides)) — mineral

Moss Agate

Silicon Dioxide with inclusions (SiO2 + Mn/Fe oxides)

Amber (Succinite (fossilized tree resin)) — mineral

Amber

Succinite (fossilized tree resin)

Moss Agate (Silicon Dioxide (SiO2) with mineral inclusions of hornblende or chlorite) — Mineral (variety of Chalcedony)

Moss Agate

Silicon Dioxide (SiO2) with mineral inclusions of hornblende or chlorite

Mineral (variety of Chalcedony)

Carnelian (Carnelian (SiO2 - Silicon Dioxide with Iron Oxide impurities)) — mineral

Carnelian

Carnelian (SiO2 - Silicon Dioxide with Iron Oxide impurities)

Jasper (Silicon dioxide (SiO2) with iron impurities) — sedimentary

Jasper

Silicon dioxide (SiO2) with iron impurities

Chert (varietal Flint or Jasper) (Silicon Dioxide (SiO2)) — sedimentary

Chert (varietal Flint or Jasper)

Silicon Dioxide (SiO2)

Jasper (specifically Red Jasper/Chert) (Silicon Dioxide (SiO2) with iron oxide inclusions) — sedimentary

Jasper (specifically Red Jasper/Chert)

Silicon Dioxide (SiO2) with iron oxide inclusions

Chert Pebble (Yellow Jasper) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert Pebble (Yellow Jasper)

Microcrystalline Quartz (SiO2)

Lazulite (Lazulite (MgAl2(PO4)2(OH)2)) — mineral

Lazulite

Lazulite (MgAl2(PO4)2(OH)2)

Dendritic Agate (Tree Agate) (Chalcedony (Silicon Dioxide, SiO2) with Manganese or Iron Oxide inclusions) — mineral

Dendritic Agate (Tree Agate)

Chalcedony (Silicon Dioxide, SiO2) with Manganese or Iron Oxide inclusions

Basaltic Tuff / Volcanic Breccia (Pyroclastic Breccia / Lithic Tuff) — igneous

Basaltic Tuff / Volcanic Breccia

Pyroclastic Breccia / Lithic Tuff

Green Moss Agate (Agate (Silicon Dioxide - SiO2) with inclusions of hornblende or chlorite) — mineral

Green Moss Agate

Agate (Silicon Dioxide - SiO2) with inclusions of hornblende or chlorite

Tree Agate (or Moss Agate) (Dendritic Agate (Silicon Dioxide - SiO2)) — mineral

Tree Agate (or Moss Agate)

Dendritic Agate (Silicon Dioxide - SiO2)

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

Pink Opal

Hydrated Silica (SiO2·nH2O)

Quartz (likely a form of massive or vein quartz) (Quartz (SiO₂)) — Mineral

Quartz (likely a form of massive or vein quartz)

Quartz (SiO₂)

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

Almandine Garnet

Almandine (Fe3Al2(SiO4)3)

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

Carnelian

Carnelian (Silicon Dioxide: SiO2)

Amber (Fossilized Tree Resin (Amorphous Hydrocarbon)) — Mineral

Amber

Fossilized Tree Resin (Amorphous Hydrocarbon)

Quartz (likely) / Siliceous rock with quartz phenocrysts (if a rock fragment) (Quartz (SiO₂)) — Mineral

Quartz (likely) / Siliceous rock with quartz phenocrysts (if a rock fragment)

Quartz (SiO₂)

Chert (Yellow or Tan variety) (Microcrystalline or cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (Yellow or Tan variety)

Microcrystalline or cryptocrystalline Quartz (SiO2)

Quartz (Quartz (SiO₂)) — Mineral

Quartz

Quartz (SiO₂)

Mixed Tumbled Gemstones and River Rocks (Mixed Decorative Stones (predominantly Silicon Dioxide - SiO2 variants)) — Mixed (Igneous, Sedimentary, Metamorphic, and Minerals)

Mixed Tumbled Gemstones and River Rocks

Mixed Decorative Stones (predominantly Silicon Dioxide - SiO2 variants)

Mixed (Igneous, Sedimentary, Metamorphic, and Minerals)

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

Quartz (Milky Quartz)

Silicon Dioxide (SiO₂)

Coal (most likely Bituminous or Anthracite) (Bituminous Coal (Grade of Coal), Anthracite (Grade of Coal)) — Sedimentary Rock

Coal (most likely Bituminous or Anthracite)

Bituminous Coal (Grade of Coal), Anthracite (Grade of Coal)

Sedimentary Rock

Garnet Schist (Garnetiferous Mica Schist) — metamorphic

Garnet Schist

Garnetiferous Mica Schist

Rough Emerald (Beryl) (Emerald (Be3Al2(SiO3)6 with Cr/V impurities)) — mineral

Rough Emerald (Beryl)

Emerald (Be3Al2(SiO3)6 with Cr/V impurities)

Garnet (Almandine variety) (Almandine, Fe3Al2(SiO4)3) — Mineral

Garnet (Almandine variety)

Almandine, Fe3Al2(SiO4)3

Hypersthene (Hypersthene ((Mg,Fe)SiO3)) — mineral

Hypersthene

Hypersthene ((Mg,Fe)SiO3)

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

Chert (often called Flint or Jasper)

Microcrystalline silica (SiO2)

Chert (Jasper/Chalcedony variety) (Silicon Dioxide (SiO2)) — sedimentary

Chert (Jasper/Chalcedony variety)

Silicon Dioxide (SiO2)

Slate (Slate (foliated metamorphic rock, primarily composed of quartz, illite, chlorite, and micas)) — metamorphic

Slate

Slate (foliated metamorphic rock, primarily composed of quartz, illite, chlorite, and micas)

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

Black Opal

Amorphous Hydrated Silica (SiO2·nH2O)

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

Pyrite (Fool's Gold)

Iron Disulfide (FeS2)

Sandstone (Sandstone (Clastic Sedimentary Rock)) — Sedimentary Rock

Sandstone

Sandstone (Clastic Sedimentary Rock)

Sedimentary Rock

Quartz (Milky/Cloudy Variety) (Silicon Dioxide (SiO2)) — mineral

Quartz (Milky/Cloudy Variety)

Silicon Dioxide (SiO2)

Quartz (Milky/Clear variety) (Silicon Dioxide (SiO2)) — mineral

Quartz (Milky/Clear variety)

Silicon Dioxide (SiO2)

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

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Agate (Chert/Chalcedony) (Silicon Dioxide (SiO2)) — mineral

Agate (Chert/Chalcedony)

Silicon Dioxide (SiO2)

Chrysanthemum Stone (Celestine (SrSO4) or Calcite (CaCO3) in Limestone/Porphyry matrix) — metamorphic

Chrysanthemum Stone

Celestine (SrSO4) or Calcite (CaCO3) in Limestone/Porphyry matrix

Petrified Wood (Silicified Wood (SiO2)) — mineral

Petrified Wood

Silicified Wood (SiO2)

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

Peridot

Olivine (Magnesium Iron Silicate - (Mg, Fe)2SiO4)