Rock Identifier

Category

Sedimentary (Biogenic)

Browse sedimentary (biogenic) specimens identified by the Rock Identifier community.

Limestone (Calcium Carbonate (CaCO3)) — sedimentary

Limestone

Calcium Carbonate (CaCO3)

Sandstone (Arenite (primarily SiO2)) — sedimentary

Sandstone

Arenite (primarily SiO2)

Sandstone (Arenite (primarily SiO2)) — sedimentary

Sandstone

Arenite (primarily SiO2)

Sandstone (Arenite (primarily SiO2)) — sedimentary

Sandstone

Arenite (primarily SiO2)

Sandstone (Ferruginous) (Arenite (with iron oxide cement)) — sedimentary

Sandstone (Ferruginous)

Arenite (with iron oxide cement)

Blue Chalcedony (Cryptocrystalline Quartz (SiO2)) — mineral

Blue Chalcedony

Cryptocrystalline Quartz (SiO2)

Chalcedony (Common Opal variant) (Silicon dioxide (SiO2) with varying levels of hydration) — mineral

Chalcedony (Common Opal variant)

Silicon dioxide (SiO2) with varying levels of hydration

Caribbean Calcite (Calcite (CaCO3) with Aragonite (CaCO3)) — mineral

Caribbean Calcite

Calcite (CaCO3) with Aragonite (CaCO3)

Quartz (Pale Rose or Milky Variety) (Silicon Dioxide (SiO2)) — mineral

Quartz (Pale Rose or Milky Variety)

Silicon Dioxide (SiO2)

Graphite (Graphite (C)) — mineral

Graphite

Graphite (C)

Iceland Spar (Optical Calcite) (Calcite (Calcium Carbonate, CaCO3)) — mineral

Iceland Spar (Optical Calcite)

Calcite (Calcium Carbonate, CaCO3)

Quartz Geode (Silicon Dioxide (SiO2)) — mineral

Quartz Geode

Silicon Dioxide (SiO2)

White Chalcedony (Agate) (Silicon Dioxide (SiO2)) — mineral

White Chalcedony (Agate)

Silicon Dioxide (SiO2)

Aragonite (Flos Ferri) (Calcium Carbonate (CaCO3)) — mineral

Aragonite (Flos Ferri)

Calcium Carbonate (CaCO3)

Quartz (Milky/Common) (Silicon Dioxide (SiO2)) — mineral

Quartz (Milky/Common)

Silicon Dioxide (SiO2)

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

Chert (or Chalcedony)

Microcrystalline Quartz (SiO2)

Carnelian Agate (Chalcedony (SiO2) with iron oxide inclusions) — mineral

Carnelian Agate

Chalcedony (SiO2) with iron oxide inclusions

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

Chert (Flint)

Microcrystalline silica (SiO2)

Kyanite (Blue or Blue-Grey) (Kyanite (Al2SiO5)) — metamorphic mineral

Kyanite (Blue or Blue-Grey)

Kyanite (Al2SiO5)

metamorphic mineral

Druzy Quartz (Silicon Dioxide (SiO2)) — mineral

Druzy Quartz

Silicon Dioxide (SiO2)

Limonite (Ironstone) (Limonite (mixture of hydrated iron oxides, primarily Goethite α-FeO(OH))) — mineral

Limonite (Ironstone)

Limonite (mixture of hydrated iron oxides, primarily Goethite α-FeO(OH))

Carnelian Agate (Silicon Dioxide (SiO2) with iron oxide impurities) — mineral

Carnelian Agate

Silicon Dioxide (SiO2) with iron oxide impurities

Magnetite (Lodestone variety) (Magnetite (Fe3O4)) — mineral

Magnetite (Lodestone variety)

Magnetite (Fe3O4)

Agate Nodule / Weathered Chert (SiO2 (Silicon Dioxide - Microcrystalline Quartz)) — Sedimentary / Mineral

Agate Nodule / Weathered Chert

SiO2 (Silicon Dioxide - Microcrystalline Quartz)

Sedimentary / Mineral

Clear Quartz (Rock Crystal) (Silicon Dioxide (SiO2)) — mineral

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Quartz (Milky Variant) (Silicon Dioxide (SiO2)) — mineral

Quartz (Milky Variant)

Silicon Dioxide (SiO2)

Clear Quartz (Rock Crystal) (Silicon Dioxide (SiO2)) — mineral

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Milky Quartz (Silicon Dioxide (SiO2)) — mineral

Milky Quartz

Silicon Dioxide (SiO2)

Blue Apatite (Apatite (Group), Ca5(PO4)3(F,Cl,OH)) — mineral

Blue Apatite

Apatite (Group), Ca5(PO4)3(F,Cl,OH)

Halite (Rock Salt) (Halite (Sodium Chloride, NaCl)) — mineral

Halite (Rock Salt)

Halite (Sodium Chloride, NaCl)

Limonite (Ochreous) (FeO(OH)·nH2O (Hydrated Iron Oxide)) — mineral

Limonite (Ochreous)

FeO(OH)·nH2O (Hydrated Iron Oxide)

Gneiss (Gneiss (High-grade metamorphic rock)) — metamorphic

Gneiss

Gneiss (High-grade metamorphic rock)

Pyrite (Fool's Gold) Cube (Iron Sulfide (FeS2)) — mineral

Pyrite (Fool's Gold) Cube

Iron Sulfide (FeS2)

Green Jasper (Silicon Dioxide (SiO2) with impurities) — sedimentary

Green Jasper

Silicon Dioxide (SiO2) with impurities

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

Flint (Chert)

Silicon Dioxide (SiO2)

Yellow Ochre / Limonite (Hydrated Iron(III) Oxide-Hydroxide (FeO(OH)·nH2O)) — mineral

Yellow Ochre / Limonite

Hydrated Iron(III) Oxide-Hydroxide (FeO(OH)·nH2O)

Chert (and Jasper/Chalcedony mixture) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (and Jasper/Chalcedony mixture)

Microcrystalline Quartz (SiO2)

Optical Calcite (Iceland Spar) (Calcium Carbonate (CaCO3)) — mineral

Optical Calcite (Iceland Spar)

Calcium Carbonate (CaCO3)

Sandstone (Arenite (primarily SiO2)) — sedimentary

Sandstone

Arenite (primarily SiO2)

Sandstone (likely Graywacke or Arkose variant) (Clastic Sedimentary Rock (SiO2 with assorted lithic fragments)) — sedimentary

Sandstone (likely Graywacke or Arkose variant)

Clastic Sedimentary Rock (SiO2 with assorted lithic fragments)

Limestone (specifically Grainstone or Micrite) (Calcium Carbonate (CaCO3)) — sedimentary

Limestone (specifically Grainstone or Micrite)

Calcium Carbonate (CaCO3)

Sandstone (Clastic sedimentary rock (primarily Quartz and Feldspar)) — sedimentary

Sandstone

Clastic sedimentary rock (primarily Quartz and Feldspar)