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.

Carnelian (Carnelian (a variety of Chalcedony, SiO2)) — Mineral

Carnelian

Carnelian (a variety of Chalcedony, SiO2)

Citrine (SiO2 (Silicon Dioxide)) — Mineral

Citrine

SiO2 (Silicon Dioxide)

Granite (with Beryl/Aquamarine) (Granite (Feldspar, Quartz, Mica, and Beryl Be3Al2Si6O18)) — igneous

Granite (with Beryl/Aquamarine)

Granite (Feldspar, Quartz, Mica, and Beryl Be3Al2Si6O18)

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)

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

Moss Agate

Silicon Dioxide (SiO2) with inclusions

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 (primarily Quartz/Chalcedony, formula: SiO2)) — sedimentary

Petrified Wood

Silicified Wood (primarily Quartz/Chalcedony, formula: SiO2)

Knightia Fossil in Limestone (Knightia eocaena in micritic limestone) — sedimentary

Knightia Fossil in Limestone

Knightia eocaena in micritic limestone

Moonstone (Orthoclase (KAlSi3O8) or Albite (NaAlSi3O8)) — mineral

Moonstone

Orthoclase (KAlSi3O8) or Albite (NaAlSi3O8)

Chert (Chert Nodule) (Silicon Dioxide (SiO2) - Microcrystalline Quartz) — sedimentary

Chert (Chert Nodule)

Silicon Dioxide (SiO2) - Microcrystalline Quartz

Turquoise, Pearl, and Coral Necklace (CuAl6(PO4)4(OH)8·4H2O (Turquoise) / CaCO3 (Pearl and Coral)) — mineral

Turquoise, Pearl, and Coral Necklace

CuAl6(PO4)4(OH)8·4H2O (Turquoise) / CaCO3 (Pearl and Coral)

Pyrite (Iron Disulfide (FeS2)) — mineral

Pyrite

Iron Disulfide (FeS2)

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

Chert (Nodule)

Silicon Dioxide (SiO2)

Chert (Jasper/Flint variety) (Microcrystalline quartz (SiO2)) — sedimentary

Chert (Jasper/Flint variety)

Microcrystalline quartz (SiO2)

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

Chert (Pink variety/Jasper)

Silicon Dioxide (SiO2)

Chert (Flint) (Chert (Microcrystalline or cryptocrystalline Quartz, SiO2)) — sedimentary

Chert (Flint)

Chert (Microcrystalline or cryptocrystalline Quartz, SiO2)

Shale (with minor calcite veining) (Clastic sedimentary rock (primarily clay minerals and quartz)) — sedimentary

Shale (with minor calcite veining)

Clastic sedimentary rock (primarily clay minerals and quartz)

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

Chert (Nodule)

Silicon Dioxide (SiO2)

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

Petrified Wood

Silicified Wood (SiO2 - Silicon Dioxide)

Obsidian (Obsidian (Volcanic Glass)) — igneous

Obsidian

Obsidian (Volcanic Glass)

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

Chert Pebble Map

Microcrystalline Quartz (SiO2)

Mica Schist (Mica Schist (predominantly Muscovite/Biotite)) — metamorphic

Mica Schist

Mica Schist (predominantly Muscovite/Biotite)

Hawk's Eye (Blue Tiger's Eye) (Quartz (fibrous crocidolite variety)) — Mineral

Hawk's Eye (Blue Tiger's Eye)

Quartz (fibrous crocidolite variety)

Prehnite (Prehnite (Ca2Al(AlSi3O10)(OH)2)) — Mineral

Prehnite

Prehnite (Ca2Al(AlSi3O10)(OH)2)

Pyrite (Iron Sulfide (FeS2)) — mineral

Pyrite

Iron Sulfide (FeS2)

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

Chert / Jasper

Microcrystalline Quartz (SiO2)

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

Chert (Jasper/Flint variety)

Silicon Dioxide (SiO2)

Pyrite (Iron Sulfide (FeS2)) — mineral

Pyrite

Iron Sulfide (FeS2)

Greenstone / Chert (Cryptocrystalline Quartz (SiO2) or Altered Basalt) — sedimentary or metamorphic

Greenstone / Chert

Cryptocrystalline Quartz (SiO2) or Altered Basalt

sedimentary or metamorphic

Jasper (likely river-worn) (Silicon Dioxide (SiO2)) — sedimentary

Jasper (likely river-worn)

Silicon Dioxide (SiO2)

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

Jasper

Jasper (Silicon Dioxide, SiO2)

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

Chert (often called Flint when dark)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Red Sandstone (Hematitic) (Clastic sedimentary rock (SiO2 with Fe2O3 inclusions)) — sedimentary

Red Sandstone (Hematitic)

Clastic sedimentary rock (SiO2 with Fe2O3 inclusions)

Baltic Amber (Butterscotch or Egg Yolk Variety) (Succinite (chemical formula: C10H16O)) — Organic Gemstone (not a rock or mineral)

Baltic Amber (Butterscotch or Egg Yolk Variety)

Succinite (chemical formula: C10H16O)

Organic Gemstone (not a rock or mineral)

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]

Rhodonite (Rhodonite (Manganese Silicate), (Mn,Fe,Mg,Ca)SiO3) — mineral

Rhodonite

Rhodonite (Manganese Silicate), (Mn,Fe,Mg,Ca)SiO3

Fancy Jasper (Silicon dioxide (SiO2)) — sedimentary

Fancy Jasper

Silicon dioxide (SiO2)

Chert (Chert Nodule with Cortex) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (Chert Nodule with Cortex)

Microcrystalline Quartz (SiO2)

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

Chert (Flint Nodules)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert (Jasper variation) (Silicon Dioxide (SiO2)) — sedimentary

Chert (Jasper variation)

Silicon Dioxide (SiO2)

Chert (varietal Chalcedony or Flint) (Silicon dioxide (SiO2) - Microcrystalline Quartz) — sedimentary

Chert (varietal Chalcedony or Flint)

Silicon dioxide (SiO2) - Microcrystalline Quartz

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

Chert (Flint variety)

Microcrystalline or Cryptocrystalline Quartz (SiO2)