Rock Identifier

Category

Sedimentary (Secondary Formation)

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

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

Chert (Agatized/Chalcedony variety)

Microcrystalline Quartz (SiO2)

Quartz Crystal (Quartz (SiO₂)) — Mineral

Quartz Crystal

Quartz (SiO₂)

Pyrite (Pyrite (FeS2)) — Mineral

Pyrite

Pyrite (FeS2)

Sandstone (Red) (Arenite (primarily Quartz, SiO2, with Iron Oxide cement)) — sedimentary

Sandstone (Red)

Arenite (primarily Quartz, SiO2, with Iron Oxide cement)

Red Shale (Lutite (primarily composed of clay minerals and iron oxides like hematite, Fe2O3)) — sedimentary

Red Shale

Lutite (primarily composed of clay minerals and iron oxides like hematite, Fe2O3)

Banded Calcite (often sold as 'Mexican Onyx' or 'Calcite Onyx') (Calcite (Calcium Carbonate, CaCO3)) — sedimentary

Banded Calcite (often sold as 'Mexican Onyx' or 'Calcite Onyx')

Calcite (Calcium Carbonate, CaCO3)

Red Sandstone (Arenite (Ferruginous Sandstone)) — sedimentary

Red Sandstone

Arenite (Ferruginous Sandstone)

Botryoidal Chalcedony with Calcite (Chalcedony (SiO2 with accessory minerals, likely CaCO3)) — Mineral

Botryoidal Chalcedony with Calcite

Chalcedony (SiO2 with accessory minerals, likely CaCO3)

Chert (and/or Flint) (Microcrystalline or cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (and/or Flint)

Microcrystalline or cryptocrystalline Quartz (SiO2)

Sandstone (Arenite (primarily SiO2)) — sedimentary

Sandstone

Arenite (primarily SiO2)

Sandstone (Arenite (primarily SiO2)) — sedimentary

Sandstone

Arenite (primarily SiO2)

Red Sandstone (Arenite (primarily Quartz with Hematite cement)) — sedimentary

Red Sandstone

Arenite (primarily Quartz with Hematite cement)

Red Jasper (Heliotrope family variant) (Silicon Dioxide with Hematite inclusions (SiO2 + Fe2O3)) — sedimentary

Red Jasper (Heliotrope family variant)

Silicon Dioxide with Hematite inclusions (SiO2 + Fe2O3)

Red Sandstone (Arenite (with Iron Oxide / Hematite cementation)) — sedimentary

Red Sandstone

Arenite (with Iron Oxide / Hematite cementation)

Travertine (Travertine (CaCO3 - Calcium Carbonate)) — sedimentary

Travertine

Travertine (CaCO3 - Calcium Carbonate)

Blue Chalcedony (Chalcedony (cryptocrystalline Silicon Dioxide, SiO2)) — mineral

Blue Chalcedony

Chalcedony (cryptocrystalline Silicon Dioxide, SiO2)

Sandstone (Arenite (primarily SiO2)) — sedimentary

Sandstone

Arenite (primarily SiO2)

Ironstone Concretion (Moqui Marble type) (Iron oxide concretion (Goethite/Hematite and Sandstone)) — sedimentary

Ironstone Concretion (Moqui Marble type)

Iron oxide concretion (Goethite/Hematite and Sandstone)

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

Chert (Flint/Chalcedony)

Microcrystalline Quartz (SiO2)

Hematite (Iron(III) oxide (Fe2O3)) — mineral

Hematite

Iron(III) oxide (Fe2O3)

Chert (often called Jasper in this color variety) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (often called Jasper in this color variety)

Microcrystalline Quartz (SiO2)

Honey Calcite (Calcium Carbonate (CaCO3)) — mineral

Honey Calcite

Calcium Carbonate (CaCO3)

Yellow Chalcedony (Agate/Jasper mix) (Silicon Dioxide (SiO2)) — mineral

Yellow Chalcedony (Agate/Jasper mix)

Silicon Dioxide (SiO2)

Nobby Hematite (Iron Ore) (Hematite (Fe2O3)) — mineral

Nobby Hematite (Iron Ore)

Hematite (Fe2O3)

Pyrite (on Quartz matrix) (Iron Disulfide (FeS2)) — mineral

Pyrite (on Quartz matrix)

Iron Disulfide (FeS2)

Jasper (Iron-rich) (Silicon Dioxide (SiO2) with Hematite (Fe2O3) impurities) — sedimentary

Jasper (Iron-rich)

Silicon Dioxide (SiO2) with Hematite (Fe2O3) impurities

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

Chert (Iron-stained)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Hematite (Iron(III) oxide (Fe2O3)) — mineral

Hematite

Iron(III) oxide (Fe2O3)

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

Chert (Jasper/Flint variety)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Hematite (Iron(III) oxide (Fe2O3)) — mineral

Hematite

Iron(III) oxide (Fe2O3)

Quartz (possibly milky quartz) (Quartz (Silica; SiO₂)) — Mineral

Quartz (possibly milky quartz)

Quartz (Silica; SiO₂)

Quartz (Silicon Dioxide (SiO₂)) — Mineral

Quartz

Silicon Dioxide (SiO₂)

Quartz (likely Rose Quartz or Milky Quartz based on color) (Quartz (SiO2 - Silicon Dioxide)) — Mineral

Quartz (likely Rose Quartz or Milky Quartz based on color)

Quartz (SiO2 - Silicon Dioxide)

Chert Pebble (Jasperoid/Flint) (Silicon Dioxide (SiO2) - cryptocrystalline quartz) — Sedimentary

Chert Pebble (Jasperoid/Flint)

Silicon Dioxide (SiO2) - cryptocrystalline quartz

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

Pyrite

Pyrite (Iron Disulfide), FeS2

Chert (Flint) (Chert (SiO2)) — sedimentary

Chert (Flint)

Chert (SiO2)

Botryoidal Black Chalcedony Geode (Black Grape Agate) (Silicon Dioxide (SiO2) - Microcrystalline Quartz) — Mineral

Botryoidal Black Chalcedony Geode (Black Grape Agate)

Silicon Dioxide (SiO2) - Microcrystalline Quartz

Orange Calcite (Calcium Carbonate (CaCO3)) — mineral

Orange Calcite

Calcium Carbonate (CaCO3)

Specular Hematite with Pyrite (Iron Oxide (Fe2O3) with Iron Sulfide (FeS2)) — mineral

Specular Hematite with Pyrite

Iron Oxide (Fe2O3) with Iron Sulfide (FeS2)

Quartz (Silicon Dioxide (SiO2)) — mineral

Quartz

Silicon Dioxide (SiO2)

Magnetite (likely with weathered Limonite/Hematite) (Magnetite (Fe3O4) with iron oxide weathering) — mineral

Magnetite (likely with weathered Limonite/Hematite)

Magnetite (Fe3O4) with iron oxide weathering

Green Fluorite (Fluorite (Calcium Fluoride) - CaF2) — mineral

Green Fluorite

Fluorite (Calcium Fluoride) - CaF2