Rock Identifier

Category

Organic Gemstone (Often Associated With Sedimentary Sequences)

Browse organic gemstone (often associated with sedimentary sequences) specimens identified by the Rock Identifier community.

Coquina Limestone (Fossiliferous Limestone) (Calcareous bioclastic sedimentary rock (CaCO3)) — sedimentary

Coquina Limestone (Fossiliferous Limestone)

Calcareous bioclastic sedimentary rock (CaCO3)

Chert (varieties: Flint or Chalcedony) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (varieties: Flint or Chalcedony)

Microcrystalline Quartz (SiO2)

Petrified Wood (Silicified wood (SiO2 - Silicon Dioxide)) — sedimentary

Petrified Wood

Silicified wood (SiO2 - Silicon Dioxide)

Chert (Gravel specimen) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (Gravel specimen)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Petrified Wood (Silicified Wood (SiO2)) — sedimentary

Petrified Wood

Silicified Wood (SiO2)

Limestone (specifically Fossiliferous or Crinoidal Limestone) (Calcium Carbonate (CaCO3) - Calcite Rock) — sedimentary

Limestone (specifically Fossiliferous or Crinoidal Limestone)

Calcium Carbonate (CaCO3) - Calcite Rock

Chert (specifically Chalcedony or Flint variation) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (specifically Chalcedony or Flint variation)

Microcrystalline Quartz (SiO2)

Coquina / Fossiliferous Limestone (Coquina (composed primarily of Calcium Carbonate / CaCO3)) — sedimentary

Coquina / Fossiliferous Limestone

Coquina (composed primarily of Calcium Carbonate / CaCO3)

Granite (Granite (felsic intrusive igneous rock)) — igneous

Granite

Granite (felsic intrusive igneous rock)

Chert (Jasper/Flint variant) (Silicon Dioxide (SiO2)) — sedimentary

Chert (Jasper/Flint variant)

Silicon Dioxide (SiO2)

Diabase (Greenstone) (Diabase (also known as Dolerite)) — igneous

Diabase (Greenstone)

Diabase (also known as Dolerite)

Limonite (Iron Stone Concretion) (Limonite (Hydrous Iron Oxide) - FeO(OH)·nH2O) — mineral

Limonite (Iron Stone Concretion)

Limonite (Hydrous Iron Oxide) - FeO(OH)·nH2O

Citrine (Silicon dioxide (SiO2)) — mineral

Citrine

Silicon dioxide (SiO2)

Turquoise (Hydrated phosphate of copper and aluminium [CuAl6(PO4)4(OH)8·4H2O]) — mineral

Turquoise

Hydrated phosphate of copper and aluminium [CuAl6(PO4)4(OH)8·4H2O]

Petrified Wood (Silicified Wood (SiO2)) — metamorphic

Petrified Wood

Silicified Wood (SiO2)

Rhodonite (Rhodonite (MnSiO3)) — Mineral

Rhodonite

Rhodonite (MnSiO3)

Turquoise (Hydrated phosphate of copper and aluminium: CuAl6(PO4)4(OH)8·4H2O) — mineral

Turquoise

Hydrated phosphate of copper and aluminium: CuAl6(PO4)4(OH)8·4H2O

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

Emerald

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

Andesite (Andesite (Intermediate Extrusive Igneous Rock)) — igneous

Andesite

Andesite (Intermediate Extrusive Igneous Rock)

Jasper, Agate, Quartz Mix (Polished Beads) (SiO₂ (Silicon Dioxide) for Quartz. Jasper and Agate are cryptocrystalline varieties of Quartz.) — Mineral/Semiprecious Gemstone (variety of Quartz)

Jasper, Agate, Quartz Mix (Polished Beads)

SiO₂ (Silicon Dioxide) for Quartz. Jasper and Agate are cryptocrystalline varieties of Quartz.

Mineral/Semiprecious Gemstone (variety of Quartz)

Diamond in Gold Setting (Diamond (C - pure carbon)) — mineral

Diamond in Gold Setting

Diamond (C - pure carbon)

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

Chert (Flint variety)

Microcrystalline Quartz (SiO2)

Chert / Flint (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert / Flint

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Pearl (Pearl (Calcium Carbonate with organic conchiolin, CaCO3)) — mineral

Pearl

Pearl (Calcium Carbonate with organic conchiolin, CaCO3)

Petrified Wood (Silicified wood (primarily Silicon Dioxide - SiO2)) — metamorphic

Petrified Wood

Silicified wood (primarily Silicon Dioxide - SiO2)

Chert (Quartz Variety) (Silicon Dioxide (SiO2)) — sedimentary

Chert (Quartz Variety)

Silicon Dioxide (SiO2)

Fossil Coral (Favosites) (Favosites (Order: Tabulata, Phylum: Cnidaria)) — sedimentary

Fossil Coral (Favosites)

Favosites (Order: Tabulata, Phylum: Cnidaria)

Fossiliferous Limestone (containing Brachiopods) (Biogenic Limestone (Calcium Carbonate, CaCO3)) — sedimentary

Fossiliferous Limestone (containing Brachiopods)

Biogenic Limestone (Calcium Carbonate, CaCO3)

Aventurine (likely Green Aventurine) (Silicon Dioxide (SiO2) with included minerals (Fuchsite for green)) — Metamorphic Rock / Mineral (Quartz Variety)

Aventurine (likely Green Aventurine)

Silicon Dioxide (SiO2) with included minerals (Fuchsite for green)

Metamorphic Rock / Mineral (Quartz Variety)

Rutilated Quartz (beads) (SiO2 with TiO2 inclusions (Titanium Dioxide inclusions within Quartz)) — Mineral

Rutilated Quartz (beads)

SiO2 with TiO2 inclusions (Titanium Dioxide inclusions within Quartz)

Smoky Quartz (SiO2 (Silicon Dioxide)) — mineral

Smoky Quartz

SiO2 (Silicon Dioxide)

Sulfur (Sulfur (S8)) — mineral

Sulfur

Sulfur (S8)

Brown Sandstone (Arenite (primarily Quartz and Feldspar, with Iron Oxide cement)) — sedimentary

Brown Sandstone

Arenite (primarily Quartz and Feldspar, with Iron Oxide cement)

Chrysocolla (Chrysocolla (Cu,Al)2H2Si2O5(OH)4·nH2O) — Mineral

Chrysocolla

Chrysocolla (Cu,Al)2H2Si2O5(OH)4·nH2O

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

Quartz Crystal Fragment

Silicon Dioxide (SiO2)

Druzy Quartz on Vesicular Basalt (Silicon Dioxide (SiO2) in an extrusive Mafic igneous host rock) — igneous

Druzy Quartz on Vesicular Basalt

Silicon Dioxide (SiO2) in an extrusive Mafic igneous host rock

Quartzite (Quartzite) — Metamorphic

Quartzite

Quartzite

Petrified Wood (Silicified Wood (SiO2)) — metamorphic

Petrified Wood

Silicified Wood (SiO2)

Tektite (Indochinite) (Tektite (High-silica natural glass)) — igneous

Tektite (Indochinite)

Tektite (High-silica natural glass)

Amber (Succinite) — mineraloid

Amber

Succinite

Quartz (pebble) (Quartz (SiO₂)) — Mineral

Quartz (pebble)

Quartz (SiO₂)

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

Petrified Wood

Silicified Wood (SiO2 permineralization)