Rock Identifier

Category

Organic Gemstone (Sedimentary Classification)

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

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

Chert (often called Flint when dark)

Chert (Microcrystalline or Cryptocrystalline Silica, SiO2)

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

Chert (often called Flint or Jasper)

Chert (Microcrystalline or Cryptocrystalline Silica, SiO2)

Black Freshwater Pearls (Biogenic Calcium Carbonate (Aragonite/Calcite), CaCO3) — mineral

Black Freshwater Pearls

Biogenic Calcium Carbonate (Aragonite/Calcite), CaCO3

Red Coral (Corallium rubrum) — mineral

Red Coral

Corallium rubrum

Amber (Succinite (C10H16O)) — Mineraloid (Organic)

Amber

Succinite (C10H16O)

Mineraloid (Organic)

Pyrite (Pyrite (Iron sulfide, FeS₂)) — Mineral

Pyrite

Pyrite (Iron sulfide, FeS₂)

Chert / Flint (Cryptocrystalline Quartz (Silicon Dioxide, SiO2)) — sedimentary

Chert / Flint

Cryptocrystalline Quartz (Silicon Dioxide, SiO2)

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

Chert / Flint

Cryptocrystalline Quartz (SiO2)

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

Chert / Flint

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Pearl (Calcium Carbonate (Aragonite) with Conchiolin; formula: CaCO3) — mineral

Pearl

Calcium Carbonate (Aragonite) with Conchiolin; formula: CaCO3

Chert (varieties include Flint and Jasper) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (varieties include Flint and Jasper)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Precious Red Coral (Corallium rubrum (Calcium Carbonate, CaCO3)) — Mineral (Organic Gemstone)

Precious Red Coral

Corallium rubrum (Calcium Carbonate, CaCO3)

Mineral (Organic Gemstone)

Shale (Mudstone (composed primarily of clay minerals like kaolinite, illite, and smectite, with quartz and calcite)) — sedimentary

Shale

Mudstone (composed primarily of clay minerals like kaolinite, illite, and smectite, with quartz and calcite)

Chert (and Chalcedony) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (and Chalcedony)

Microcrystalline Quartz (SiO2)

Amber (Succinicum (Organic polymer, largely C10H16O)) — Organic Mineral

Amber

Succinicum (Organic polymer, largely C10H16O)

Organic Mineral

Pyrite (Iron Sulfide (FeS2)) — mineral

Pyrite

Iron Sulfide (FeS2)

Amber (Succinite (fossilized resin)) — mineral

Amber

Succinite (fossilized resin)

Fossiliferous Limestone with Rugose Coral (Calcite (CaCO3) matrix containing Rugosa (order of extinct solitary and colonial corals)) — sedimentary

Fossiliferous Limestone with Rugose Coral

Calcite (CaCO3) matrix containing Rugosa (order of extinct solitary and colonial corals)

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

Moss Agate

Chalcedony (SiO2) with inclusions of manganese or iron oxide

Coal (most likely Bituminous or Anthracite) (Coal (organic sedimentary rock)) — Sedimentary

Coal (most likely Bituminous or Anthracite)

Coal (organic sedimentary rock)

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

Chert (Jasper variation)

Chert (SiO2)

Coal (likely Bituminous or Lignite) (Organic Sedimentary Rock (Carbonaceous)) — sedimentary

Coal (likely Bituminous or Lignite)

Organic Sedimentary Rock (Carbonaceous)

Shungite (Non-crystalline carbonoid (Shungite)) — metamorphic

Shungite

Non-crystalline carbonoid (Shungite)

Fossil Crab (Decapoda (likely Avitelmessus or Raninidae family)) — sedimentary

Fossil Crab

Decapoda (likely Avitelmessus or Raninidae family)

Amber (Dark/Black Variety) (Succinite (Resinite), C10H16O) — mineral

Amber (Dark/Black Variety)

Succinite (Resinite), C10H16O

Pearl (Calcium Carbonate (CaCO3) - Aragonite/Calcite) — mineral

Pearl

Calcium Carbonate (CaCO3) - Aragonite/Calcite

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

Chert (Chert Nodule with Chalky Cortex)

Silicon Dioxide (SiO2) - Microcrystalline Quartz

Jasper containing fossilized inclusions (Silicon Dioxide (SiO2) with trace impurities and biogenic inclusions) — sedimentary

Jasper containing fossilized inclusions

Silicon Dioxide (SiO2) with trace impurities and biogenic inclusions

Amber (Succinite) — Mineraloid

Amber

Succinite

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

Moss Agate

Chalcedony (Silicon Dioxide - SiO2) with inclusions

Granite (Granite (a broadly defined plutonic igneous rock, often more specifically classified as quartz monzonite or granodiorite based on precise mineral percentages)) — igneous

Granite

Granite (a broadly defined plutonic igneous rock, often more specifically classified as quartz monzonite or granodiorite based on precise mineral percentages)

Amber (Succinite (Approximate formula: C10H16O)) — Mineraloid

Amber

Succinite (Approximate formula: C10H16O)

Pearl (with Peridot) (Calcium carbonate (CaCO3) + Conchiolin; Peridot: Magnesium iron silicate (Mg, Fe)2SiO4) — mineral

Pearl (with Peridot)

Calcium carbonate (CaCO3) + Conchiolin; Peridot: Magnesium iron silicate (Mg, Fe)2SiO4

Shungite (Non-crystalline carbon (allotrope of carbon)) — metamorphic

Shungite

Non-crystalline carbon (allotrope of carbon)

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

Moss Agate

Chalcedony (Silicon Dioxide, SiO2) with inclusions

Black Pearl (Tahitian-style Cultured Pearl) (Calcium Carbonate (Aragonite) with Conchiolin (CaCO3)) — mineral

Black Pearl (Tahitian-style Cultured Pearl)

Calcium Carbonate (Aragonite) with Conchiolin (CaCO3)

Amber (Succinite (C10H16O)) — mineral

Amber

Succinite (C10H16O)

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

Moss Agate / Chalcedony

Silicon Dioxide (SiO2)

Shale (Clastic sedimentary rock (primarily clay and silt minerals)) — sedimentary

Shale

Clastic sedimentary rock (primarily clay and silt minerals)

Sandstone Concretion with Fossil Wood (Ferruginous Sandstone Concretion (SiO2 with Fe2O3 cement)) — sedimentary

Sandstone Concretion with Fossil Wood

Ferruginous Sandstone Concretion (SiO2 with Fe2O3 cement)

Dendritic Limestone (Calcite with Manganese Oxide (Manganese Dendrites)) — sedimentary

Dendritic Limestone

Calcite with Manganese Oxide (Manganese Dendrites)

Pearl (Biogenic Calcium Carbonate (Aragonite/Calcite), CaCO3) — mineral

Pearl

Biogenic Calcium Carbonate (Aragonite/Calcite), CaCO3