Rock Identifier

Category

Sedimentary (Secondary Mineral Formation)

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

Crushed Granite Gravel (Granite (composed primarily of Quartz, Alkali Feldspar, and Plagioclase Feldspar)) — igneous

Crushed Granite Gravel

Granite (composed primarily of Quartz, Alkali Feldspar, and Plagioclase Feldspar)

Orange Quartzite (Quartzite (primarily SiO2 with Hematite impurities)) — metamorphic

Orange Quartzite

Quartzite (primarily SiO2 with Hematite impurities)

Red Quartzite (Ferruginous Quartz) (Quartzite (SiO2 with Fe2O3 inclusions)) — metamorphic

Red Quartzite (Ferruginous Quartz)

Quartzite (SiO2 with Fe2O3 inclusions)

Ferruginous Quartzite (Red Sandstone/Quartzite) (Quartzite with Iron inclusions (SiO2 + Fe2O3)) — metamorphic

Ferruginous Quartzite (Red Sandstone/Quartzite)

Quartzite with Iron inclusions (SiO2 + Fe2O3)

Milky Quartz (Silicon Dioxide (SiO2)) — mineral

Milky Quartz

Silicon Dioxide (SiO2)

Basalt (Mafic Volcanic Rock (composed of Plagioclase Feldspar and Pyroxene)) — igneous

Basalt

Mafic Volcanic Rock (composed of Plagioclase Feldspar and Pyroxene)

Tiger's Eye (Polished Point/Tower) (SiO2 (Silicon Dioxide) with included crocidolite fibers) — Mineral (Metamorphic pseudomorph)

Tiger's Eye (Polished Point/Tower)

SiO2 (Silicon Dioxide) with included crocidolite fibers

Mineral (Metamorphic pseudomorph)

Tiger's Eye (Pseudomorph of Quartz after Crocidolite (SiO2 with iron inclusions)) — metamorphic

Tiger's Eye

Pseudomorph of Quartz after Crocidolite (SiO2 with iron inclusions)

Yellow Calcite (Calcium Carbonate (CaCO3)) — mineral

Yellow Calcite

Calcium Carbonate (CaCO3)

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

Gneiss

Gneiss (High-grade metamorphic rock)

Quartzite (Yellow/Iron-Stained) (Quartzite (SiO2 with Iron Oxide impurities)) — metamorphic

Quartzite (Yellow/Iron-Stained)

Quartzite (SiO2 with Iron Oxide impurities)

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

Gneiss

Gneiss (High-grade metamorphic rock)

Biotite Mica (K(Mg,Fe)3AlSi3O10(OH)2) — Mineral in a matrix (likely quartz or feldspar)

Biotite Mica

K(Mg,Fe)3AlSi3O10(OH)2

Mineral in a matrix (likely quartz or feldspar)

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

Sandstone (Micaceous)

Arenite (composed primarily of SiO2)

Pyrite (Iron Sulfide (FeS2)) — mineral

Pyrite

Iron Sulfide (FeS2)

Tiger's Eye (Pseudomorph of Quartz after Crocidolite (SiO2 with iron inclusions)) — metamorphic

Tiger's Eye

Pseudomorph of Quartz after Crocidolite (SiO2 with iron inclusions)

Magnetite (Magnetite (Fe3O4)) — mineral

Magnetite

Magnetite (Fe3O4)

Agate (specifically, multi-colored or pastel-dyed agate) (Silicon dioxide (SiO2) - specifically, a cryptocrystalline variety of quartz known as Chalcedony, with banding classified as Agate. (If it were Fluorite, the chemical formula would be Calcium Fluoride - CaF2).) — Mineral

Agate (specifically, multi-colored or pastel-dyed agate)

Silicon dioxide (SiO2) - specifically, a cryptocrystalline variety of quartz known as Chalcedony, with banding classified as Agate. (If it were Fluorite, the chemical formula would be Calcium Fluoride - CaF2).

Agate (Silicon Dioxide (SiO2)) — mineral

Agate

Silicon Dioxide (SiO2)

Carnelian (Carnelian (variety of Chalcedony, SiO2)) — mineral

Carnelian

Carnelian (variety of Chalcedony, SiO2)

Ironstone (likely Limonite or Goethite nodule) (Hydrothermally altered Ferric Hydroxide (FeO(OH)·nH2O)) — sedimentary

Ironstone (likely Limonite or Goethite nodule)

Hydrothermally altered Ferric Hydroxide (FeO(OH)·nH2O)

Ironstone Concretions (Ironstone) (Ferruginous Sandstone or Siltstone (Fe2O3)) — sedimentary

Ironstone Concretions (Ironstone)

Ferruginous Sandstone or Siltstone (Fe2O3)

Blue Tiger's Eye (Riebeckite (crocidolite variety)) — Mineral

Blue Tiger's Eye

Riebeckite (crocidolite variety)

Quartz Geode (Silicon Dioxide (SiO2)) — mineral

Quartz Geode

Silicon Dioxide (SiO2)

Satin Spar (often sold as Selenite) (Gypsum (CaSO4·2H2O)) — mineral

Satin Spar (often sold as Selenite)

Gypsum (CaSO4·2H2O)

Granite (Granite (a plutonic igneous rock)) — Igneous

Granite

Granite (a plutonic igneous rock)

Sandstone (Arenite (SiO2 principal)) — sedimentary

Sandstone

Arenite (SiO2 principal)

Sandstone (Arenite) — sedimentary

Sandstone

Arenite

Banded Gneiss (Gneiss (Metamorphic Rock)) — metamorphic

Banded Gneiss

Gneiss (Metamorphic Rock)

Tiger's Eye (Blue-Gold transition) (Pseudomorph of Quartz after Crocidolite (SiO2)) — metamorphic

Tiger's Eye (Blue-Gold transition)

Pseudomorph of Quartz after Crocidolite (SiO2)

Sandstone (Arenite (SiO2 based)) — sedimentary

Sandstone

Arenite (SiO2 based)

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

Sandstone

Arenite (composed primarily of SiO2)

Breciated Limestone with Calcite Veins (Sedimentary Breccia (CaCO3)) — sedimentary

Breciated Limestone with Calcite Veins

Sedimentary Breccia (CaCO3)

Red Quartzite River Stone (Metamorphic Rock (composed mainly of Quartz, SiO2)) — metamorphic

Red Quartzite River Stone

Metamorphic Rock (composed mainly of Quartz, SiO2)

Sandstone (with Concretion) (Arenite / Quartzose Sandstone) — sedimentary

Sandstone (with Concretion)

Arenite / Quartzose Sandstone

Jadeite (NaAlSi2O6 (Sodium Aluminum Silicate)) — metamorphic

Jadeite

NaAlSi2O6 (Sodium Aluminum Silicate)

Granite (weathered pebble) (Granite (plutonic igneous rock)) — Igneous

Granite (weathered pebble)

Granite (plutonic igneous rock)

Shale (Shale (clastic sedimentary rock)) — Sedimentary

Shale

Shale (clastic sedimentary rock)

Sandstone (Banded) (Clastic Sedimentary Rock (primarily SiO2)) — sedimentary

Sandstone (Banded)

Clastic Sedimentary Rock (primarily SiO2)

Sandstone (Banded) (Clastic sedimentary rock (primarily SiO2)) — sedimentary

Sandstone (Banded)

Clastic sedimentary rock (primarily SiO2)

Milky Quartz (Silicon Dioxide (SiO2)) — mineral

Milky Quartz

Silicon Dioxide (SiO2)

Green Aventurine (Green Quartzite) (Silicon Dioxide (SiO2) with inclusions of Fuchsite (K(Al,Cr)2(AlSi3O10)(OH)2)) — metamorphic

Green Aventurine (Green Quartzite)

Silicon Dioxide (SiO2) with inclusions of Fuchsite (K(Al,Cr)2(AlSi3O10)(OH)2)