Rock Identifier

Category

Mineral (Organic)

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

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

Chert / Flint

Chert (Silicon Dioxide, SiO2)

Petrified Wood (Silicified Wood (SiO2)) — mineral

Petrified Wood

Silicified Wood (SiO2)

Fossil Shell (Bivalve) (Class Bivalvia (Likely a member of the Ostreidae or Gryphaeidae family), CaCO3) — sedimentary

Fossil Shell (Bivalve)

Class Bivalvia (Likely a member of the Ostreidae or Gryphaeidae family), CaCO3

Brachiopod Fossil in Limestone (Phylum Brachiopoda (likely Order Spiriferida), CaCO3 (Calcite)) — sedimentary

Brachiopod Fossil in Limestone

Phylum Brachiopoda (likely Order Spiriferida), CaCO3 (Calcite)

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

Petrified Wood

Silicified Wood (primarily SiO₂ - Silicon Dioxide)

Jasper (Green/Yellow Moss Jasper) (Silicon Dioxide (SiO2)) — mineral

Jasper (Green/Yellow Moss Jasper)

Silicon Dioxide (SiO2)

Chert (Jasper/Common Opal mix) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (Jasper/Common Opal mix)

Microcrystalline Quartz (SiO2)

Limestone with Chert or Siltstone bands (Sedimentary carbonate rock (CaCO3) often with siliceous impurities) — sedimentary

Limestone with Chert or Siltstone bands

Sedimentary carbonate rock (CaCO3) often with siliceous impurities

Chert (specifically Yellow/Tan Chert) (Silicon Dioxide (SiO2)) — sedimentary

Chert (specifically Yellow/Tan Chert)

Silicon Dioxide (SiO2)

Ironstone Concretion (Limonite/Hematite Nodules) (Ironstone (principally Limonite FeO(OH)·nH2O or Hematite Fe2O3 mixed with silica/clay)) — sedimentary

Ironstone Concretion (Limonite/Hematite Nodules)

Ironstone (principally Limonite FeO(OH)·nH2O or Hematite Fe2O3 mixed with silica/clay)

Chert (White Chert / Flint) (Microcrystalline or Cryptocrystalline Silicon Dioxide (SiO2)) — sedimentary

Chert (White Chert / Flint)

Microcrystalline or Cryptocrystalline Silicon Dioxide (SiO2)

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

Chert (Flint)

Chert (Silicon Dioxide, SiO2)

Dendritic Agate (or Dendritic Opal) (SiO2 (for Agate), SiO2·nH2O (for Opal)) — Mineral

Dendritic Agate (or Dendritic Opal)

SiO2 (for Agate), SiO2·nH2O (for Opal)

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

Chert (Jasper/Flint variety)

Microcrystalline Quartz (SiO2)

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

Chert (Flint)

Chert (Microcrystalline Quartz, SiO2)

Petrified Wood (Silicified Wood (SiO2 - Quartz/Chalcedony replacement)) — Mineral / Fossil

Petrified Wood

Silicified Wood (SiO2 - Quartz/Chalcedony replacement)

Mineral / Fossil

Sandstone (Arenite (primarily composed of SiO2)) — sedimentary

Sandstone

Arenite (primarily composed of SiO2)

Zebra Marble (Metamorphosed Alabaster/Limestone (CaCO3)) — metamorphic

Zebra Marble

Metamorphosed Alabaster/Limestone (CaCO3)

Picture Jasper (Silicon Dioxide (SiO2) - Opaque Chert/Quartzite variety) — sedimentary

Picture Jasper

Silicon Dioxide (SiO2) - Opaque Chert/Quartzite variety

Septarian Nodule (Septarian Concretion) — sedimentary

Septarian Nodule

Septarian Concretion

Carnelian (Orange Chalcedony) (Silicon Dioxide (SiO2)) — mineral

Carnelian (Orange Chalcedony)

Silicon Dioxide (SiO2)

Limestone (Concretionary or Tufa) (Calcium Carbonate (CaCO3)) — sedimentary

Limestone (Concretionary or Tufa)

Calcium Carbonate (CaCO3)

Chert (specifically Flint or Common Chert) (Chert (Cryptocrystalline Silica, SiO2)) — sedimentary

Chert (specifically Flint or Common Chert)

Chert (Cryptocrystalline Silica, SiO2)

Moss Agate (Silicon Dioxide (SiO2) with inclusions of manganese or iron oxides) — Mineral (Variety of Chalcedony)

Moss Agate

Silicon Dioxide (SiO2) with inclusions of manganese or iron oxides

Mineral (Variety of Chalcedony)

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

Pyrite

Pyrite (Iron sulfide, FeS₂)

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)

Chert (Nodule) (Chert (composition: SiO2)) — sedimentary

Chert (Nodule)

Chert (composition: SiO2)

Chert (often called Flint) (Chert (Microcrystalline Quartz, SiO2)) — sedimentary

Chert (often called Flint)

Chert (Microcrystalline Quartz, SiO2)

Jasper (Brown Iron-Rich Variety) (Silicon Dioxide (SiO2) with Fe2O3 (Iron Oxide/Crystalline Quartz)) — sedimentary

Jasper (Brown Iron-Rich Variety)

Silicon Dioxide (SiO2) with Fe2O3 (Iron Oxide/Crystalline Quartz)

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

Banded Chert (Flint/Jasper variety)

Microcrystalline Quartz (SiO2)

Banded Chert (Cryptocrystalline Quartz (SiO2)) — sedimentary

Banded Chert

Cryptocrystalline Quartz (SiO2)

Sandstone (likely Fossilized Wood or Concrete Simulacrum) (Arenite / Silicified Wood / Anthropogenic Concrete) — sedimentary

Sandstone (likely Fossilized Wood or Concrete Simulacrum)

Arenite / Silicified Wood / Anthropogenic Concrete

Petrified Wood (Silicified Wood (SiO2)) — sedimentary

Petrified Wood

Silicified Wood (SiO2)

Orthoceras Fossil in Limestone (Orthoceras (extinct genus of cephalopods) in Carboniferous or Devonian Limestone) — sedimentary

Orthoceras Fossil in Limestone

Orthoceras (extinct genus of cephalopods) in Carboniferous or Devonian Limestone

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

Chert (Jasper/Limonitic Chert)

Microcrystalline Quartz (SiO2)

Petrified Wood (Silicified Wood (SiO2)) — sedimentary

Petrified Wood

Silicified Wood (SiO2)

Ferruginous Chert (Microcrystalline Quartz (SiO2) with Iron Oxides) — sedimentary

Ferruginous Chert

Microcrystalline Quartz (SiO2) with Iron Oxides

Fossilized Crinoid Stem Segment (Crinoid (Phylum Echinodermata, Class Crinoidea)) — sedimentary

Fossilized Crinoid Stem Segment

Crinoid (Phylum Echinodermata, Class Crinoidea)

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

Moss Agate

Chalcedony (Silicon Dioxide with inclusions) - SiO2

Chert (Red Jasper variant) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (Red Jasper variant)

Microcrystalline Quartz (SiO2)

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

Chert (Nodule)

Silicon Dioxide (SiO2)