Rock Identifier

Category

Organic (Anthropogenic)

Browse organic (anthropogenic) specimens identified by the Rock Identifier community.

Chert (White Chert/Flint) (Chert (SiO2)) — sedimentary

Chert (White Chert/Flint)

Chert (SiO2)

Petrified Wood (Silicified Wood (primarily SiO2)) — metamorphic

Petrified Wood

Silicified Wood (primarily SiO2)

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

Herkimer Diamond

Quartz (Silica - SiO2)

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

Chert (Gravel)

Microcrystalline Quartz (SiO2)

Limestone (specifically fossiliferous/skeletal limestone) (Calcium Carbonate (CaCO3)) — sedimentary

Limestone (specifically fossiliferous/skeletal limestone)

Calcium Carbonate (CaCO3)

Fossil Shell (Bivalve) (Phylum Mollusca, Class Bivalvia (typically composed of Calcium Carbonate / CaCO3)) — sedimentary

Fossil Shell (Bivalve)

Phylum Mollusca, Class Bivalvia (typically composed of Calcium Carbonate / CaCO3)

Chert (Smooth River Pebble) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (Smooth River Pebble)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

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

Chert (Jasper/Chalcedony variety)

Microcrystalline Quartz (SiO2)

Chert (White-Grey variety) (Microcrystalline or cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (White-Grey variety)

Microcrystalline or cryptocrystalline Quartz (SiO2)

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

Red Chert (Jasper)

Silicon Dioxide (SiO2) with iron oxide inclusions

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

Chert (Quartz Variety)

Chert (SiO2)

Chert (Light Grey / Flint variant) (Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (Light Grey / Flint variant)

Cryptocrystalline Quartz (SiO2)

Chert (Brecciated River Cobble) (Silicon Dioxide (SiO2)) — sedimentary

Chert (Brecciated River Cobble)

Silicon Dioxide (SiO2)

Chert (Jasper-rich) (Silicon dioxide (SiO2) - Microcrystalline Quartz) — sedimentary

Chert (Jasper-rich)

Silicon dioxide (SiO2) - Microcrystalline Quartz

Banded Chert (River Stone/Cobble) (Microcrystalline Quartz (SiO2)) — sedimentary

Banded Chert (River Stone/Cobble)

Microcrystalline Quartz (SiO2)

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

Chert (Quartz Variety)

Chert (mostly SiO2 / Silicon Dioxide)

Chert (with Lichen) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (with Lichen)

Microcrystalline Quartz (SiO2)

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

Red Chert (Jasper)

Silicon Dioxide (SiO2)

Chert (specifically Banded Chert) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (specifically Banded Chert)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

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

Chert (Nodule)

Microcrystalline Quartz (SiO2)

Jasper (Petrified Wood variant) (Silicon Dioxide (SiO2) with iron oxide inclusions) — sedimentary

Jasper (Petrified Wood variant)

Silicon Dioxide (SiO2) with iron oxide inclusions

Chert (often called Flint or Jasper when pigmented) (Microcrystalline or cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (often called Flint or Jasper when pigmented)

Microcrystalline or cryptocrystalline Quartz (SiO2)

Sandstone (likely Arkose or Quartz Sandstone) (Arenite (SiO2 principal component)) — sedimentary

Sandstone (likely Arkose or Quartz Sandstone)

Arenite (SiO2 principal component)

Chert (and Petrified Wood) (Silicon Dioxide (SiO2)) — sedimentary

Chert (and Petrified Wood)

Silicon Dioxide (SiO2)

Chert (specifically Flint or Common Chert) (Silicon Dioxide (SiO2)) — sedimentary

Chert (specifically Flint or Common Chert)

Silicon Dioxide (SiO2)

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

Chert (and Flint)

Silicon Dioxide (SiO2)

Chert (Pebble) (Microcrystalline silica (SiO2)) — sedimentary

Chert (Pebble)

Microcrystalline silica (SiO2)

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

Greenstone / Chert

Cryptocrystalline Quartz (SiO2) or Altered Basalt

sedimentary or metamorphic

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

Chert (Jasper/Flint variety)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert (variations include Flint) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (variations include Flint)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Ironstone Concretion (Iron-rich Mudstone) (Siderite / Geothite concretion (FeCO3 / FeO(OH))) — sedimentary

Ironstone Concretion (Iron-rich Mudstone)

Siderite / Geothite concretion (FeCO3 / FeO(OH))

Chert (with Quartz veins) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (with Quartz veins)

Microcrystalline Quartz (SiO2)

Fossil Coral (Rugosa or Solitary Coral) (Rugosa (Order), often referred to as 'Horn Coral' (Lithostrotionella or Grewingkia)) — sedimentary

Fossil Coral (Rugosa or Solitary Coral)

Rugosa (Order), often referred to as 'Horn Coral' (Lithostrotionella or Grewingkia)

Chert (Holey Stone) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (Holey Stone)

Microcrystalline Quartz (SiO2)

Amber (Succinite (Carbon-based organic compound; approximate formula C10H16O)) — Mineraloid

Amber

Succinite (Carbon-based organic compound; approximate formula C10H16O)

Ironstone Concretion (Ironstone Gourd) (Limonite/Goethite Concretion (FeOO(H))) — sedimentary

Ironstone Concretion (Ironstone Gourd)

Limonite/Goethite Concretion (FeOO(H))

Chert (Nodule) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (Nodule)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

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

Pink Opal

Hydrated silicon dioxide (SiO2·nH2O) with inclusions

Limestone (Calcium Carbonate (CaCO3)) — sedimentary

Limestone

Calcium Carbonate (CaCO3)

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

Moss Agate

Silicon Dioxide with inclusions (SiO2 + impurities)

Amber / Copal (Succinite (fossilized resin)) — mineraloid

Amber / Copal

Succinite (fossilized resin)

Shale or Siltstone (Sedimentary Clastic Rock (Variable mineral composition including quartz and clay minerals)) — sedimentary

Shale or Siltstone

Sedimentary Clastic Rock (Variable mineral composition including quartz and clay minerals)