Rock Identifier

Category

Organic Mineral

Browse organic mineral specimens identified by the Rock Identifier community.

Petrified Wood (Calamites Fossil) (Calamites sp. (Silicified/Permineralized Plant Fossil)) — sedimentary

Petrified Wood (Calamites Fossil)

Calamites sp. (Silicified/Permineralized Plant Fossil)

Petrified Wood (Silicified Wood (primarily Quartz/Chalcedony, SiO2)) — sedimentary

Petrified Wood

Silicified Wood (primarily Quartz/Chalcedony, SiO2)

Peacock Ore (Bornite (Cu5FeS4) or Chalcopyrite (CuFeS2) with iridescent tarnish) — mineral

Peacock Ore

Bornite (Cu5FeS4) or Chalcopyrite (CuFeS2) with iridescent tarnish

Asphalt / Bituminous Aggregate (Bituminous mixture (Hydrocarbon-based sediment)) — sedimentary

Asphalt / Bituminous Aggregate

Bituminous mixture (Hydrocarbon-based sediment)

Quartz Geode (Silicon Dioxide (SiO2)) — sedimentary

Quartz Geode

Silicon Dioxide (SiO2)

Petrified Wood (Silicified Wood (primarily Quartz/Chalcedony, formula SiO2)) — sedimentary

Petrified Wood

Silicified Wood (primarily Quartz/Chalcedony, formula SiO2)

Picture Jasper (Silicon Dioxide (SiO2) with iron oxide and organic impurities) — sedimentary

Picture Jasper

Silicon Dioxide (SiO2) with iron oxide and organic impurities

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

Chert (Jasper/Flint variety)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Shale (Fissile mudrock (composed primarily of clay minerals and quartz)) — sedimentary

Shale

Fissile mudrock (composed primarily of clay minerals and quartz)

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

Chert (Flint variety)

Microcrystalline context of Quartz (SiO2)

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

Chert (Flint)

Silicon Dioxide (SiO2)

Chert (Jasper) (Microcrystalline Silica (SiO2)) — sedimentary

Chert (Jasper)

Microcrystalline Silica (SiO2)

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

Chert Pebble (Jasper/Quartz variety)

Microcrystalline Quartz (SiO2)

Ironstone Concretion (Limonite/Goethite) (Iron oxide concretion (contains FeO(OH)·nH2O)) — sedimentary

Ironstone Concretion (Limonite/Goethite)

Iron oxide concretion (contains FeO(OH)·nH2O)

Mixed Quartz and Jasper Pebbles (Silicon Dioxide (SiO2)) — Mineral

Mixed Quartz and Jasper Pebbles

Silicon Dioxide (SiO2)

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

Chert / Chalcedony

Silicon Dioxide (SiO2)

Shale (or Mudstone) (Siltstone/Argillite (composed mainly of clay and silt-sized particles)) — sedimentary

Shale (or Mudstone)

Siltstone/Argillite (composed mainly of clay and silt-sized particles)

Amber (Succinite (specifically for Baltic amber); Approximate formula: C10H16O) — Organic Gemstone (Mineraloid)

Amber

Succinite (specifically for Baltic amber); Approximate formula: C10H16O

Organic Gemstone (Mineraloid)

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

Green Moss Agate

Silicon Dioxide (SiO2) with inclusions of hornblende or chlorite

Chert (Iron-stained) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (Iron-stained)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

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

Pink Opal (Common Opal)

Amorphous Hydrated Silica (SiO2·nH2O)

Black Marble (Recrystallized Calcite (CaCO3)) — metamorphic

Black Marble

Recrystallized Calcite (CaCO3)

Chert (specifically Gray/Black Chert) (Chert (Microcrystalline or Cryptocrystalline Quartz, SiO2)) — sedimentary

Chert (specifically Gray/Black Chert)

Chert (Microcrystalline or Cryptocrystalline Quartz, SiO2)

Chert / River Pebble (Silicon Dioxide (SiO2)) — sedimentary

Chert / River Pebble

Silicon Dioxide (SiO2)

Pyrite (Iron Sulfide (FeS2)) — mineral

Pyrite

Iron Sulfide (FeS2)

Herkimer Diamond (Quartz (Silica - SiO2)) — mineral

Herkimer Diamond

Quartz (Silica - SiO2)

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

Chert (often called Flint or Jasper if reddish)

Microcrystalline Quartz (SiO2)

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

Moss Agate

Silicon Dioxide (SiO2) with inclusions

Pyrite in Limestone (Iron Sulfide (FeS2) in Calcium Carbonate (CaCO3)) — mineral

Pyrite in Limestone

Iron Sulfide (FeS2) in Calcium Carbonate (CaCO3)

Pearl (Calcium Carbonate (mostly Aragonite), CaCO3 (with conchiolin)) — mineral

Pearl

Calcium Carbonate (mostly Aragonite), CaCO3 (with conchiolin)

Chalcedony (Botryoidal or Tumbled) (Chalcedony (SiO₂)) — mineral

Chalcedony (Botryoidal or Tumbled)

Chalcedony (SiO₂)

Pink Opal (Hydrated silicon dioxide (SiO2·nH2O) with inclusions) — mineral

Pink Opal

Hydrated silicon dioxide (SiO2·nH2O) with inclusions

Septarian Nodule (Dragon Stone) (Septarian concretion (composition: CaCO3 - Calcite, Aragonite, and Siderite/Limestone)) — sedimentary

Septarian Nodule (Dragon Stone)

Septarian concretion (composition: CaCO3 - Calcite, Aragonite, and Siderite/Limestone)

Shale or Slaty Mudstone (Argillaceous sedimentary rock) — sedimentary

Shale or Slaty Mudstone

Argillaceous sedimentary rock

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

Chert (Flint)

Microcrystalline Quartz (SiO2)

Petrified Wood (Silicified Wood (SiO2)) — sedimentary

Petrified Wood

Silicified Wood (SiO2)

Coral Fossil (Scleractinia) (Scleractinia (Order), primarily CaCO3 (Aragonite or Calcite)) — sedimentary

Coral Fossil (Scleractinia)

Scleractinia (Order), primarily CaCO3 (Aragonite or Calcite)

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

Red Jasper

Silicon Dioxide (SiO2) with iron oxide inclusions

Petrified Wood (Silicified Wood (SiO2)) — sedimentary

Petrified Wood

Silicified Wood (SiO2)

Petrified Wood (Silicified Wood (SiO2)) — sedimentary

Petrified Wood

Silicified Wood (SiO2)

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

Pearl

Pearl (Calcium Carbonate with organic conchiolin, CaCO3)

Petrified Wood (Silicified Wood / Chalcedony (SiO2)) — mineral

Petrified Wood

Silicified Wood / Chalcedony (SiO2)