Rock Identifier

Category

Mineraloid (Man Made)

Browse mineraloid (man made) specimens identified by the Rock Identifier community.

Limonite (Iron Ore) (Limonite (FeO(OH)·nH2O)) — mineral

Limonite (Iron Ore)

Limonite (FeO(OH)·nH2O)

Obsidian (Amorphous volcanic glass (SiO2)) — igneous

Obsidian

Amorphous volcanic glass (SiO2)

Limonite (Iron Stone/Goethite) (Limonite (mixture of hydrated iron oxides, primarily Goethite: α-FeO(OH))) — mineral

Limonite (Iron Stone/Goethite)

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

Limonitic Iron Ore / Goethite (Hydrated Iron(III) oxide-hydroxide (primarily FeO(OH)·nH2O)) — sedimentary

Limonitic Iron Ore / Goethite

Hydrated Iron(III) oxide-hydroxide (primarily FeO(OH)·nH2O)

Amber (Succinite (with a generalized formula of C10H16O)) — mineral

Amber

Succinite (with a generalized formula of C10H16O)

Black Obsidian (Obsidian (Volcanic Glass), primarily SiO2 (Silicon Dioxide)) — igneous

Black Obsidian

Obsidian (Volcanic Glass), primarily SiO2 (Silicon Dioxide)

Obsidian (Obsidian (Extrusive Volcanic Glass)) — igneous

Obsidian

Obsidian (Extrusive Volcanic Glass)

Limonite (Iron Ore) (Limonite (an FeO(OH)·nH2O mineraloid, not a true mineral due to variable composition)) — Mineral

Limonite (Iron Ore)

Limonite (an FeO(OH)·nH2O mineraloid, not a true mineral due to variable composition)

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

Sandstone

Arenite (composed primarily of Quartz: SiO2)

Mahogany Obsidian Arrowhead (Volcanic Glass with Hematite/Magnetite inclusions (Amorphous Silicon Dioxide)) — igneous

Mahogany Obsidian Arrowhead

Volcanic Glass with Hematite/Magnetite inclusions (Amorphous Silicon Dioxide)

Red Sandstone (Arenite (Ferruginous Sandstone)) — sedimentary

Red Sandstone

Arenite (Ferruginous Sandstone)

Sandstone (Pebble) (Sandstone (arenite, arkose, wacke depending on composition)) — sedimentary

Sandstone (Pebble)

Sandstone (arenite, arkose, wacke depending on composition)

Quartzite (Metamorphic Rock (Mainly SiO2)) — metamorphic

Quartzite

Metamorphic Rock (Mainly SiO2)

Diabase (Greenstone) (Diabase (Dolerite)) — igneous

Diabase (Greenstone)

Diabase (Dolerite)

Obsidian (Black) (Obsidian (High-silica volcanic glass)) — igneous

Obsidian (Black)

Obsidian (High-silica volcanic glass)

Sandstone (specifically Arkose or Quartz Arenite) (Arenite (primarily SiO2 with possible Feldspar)) — sedimentary

Sandstone (specifically Arkose or Quartz Arenite)

Arenite (primarily SiO2 with possible Feldspar)

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

Red Sandstone

Arenite (with Iron Oxide / Hematite staining)

Ferruginous Sandstone (Ironstone) (Clastic Sedimentary Rock (composed of SiO2 with Fe2O3/FeO(OH) cement)) — sedimentary

Ferruginous Sandstone (Ironstone)

Clastic Sedimentary Rock (composed of SiO2 with Fe2O3/FeO(OH) cement)

Bog Iron / Limonite Concretion (Goethite/Limonite mixture (FeO(OH)·nH2O)) — sedimentary

Bog Iron / Limonite Concretion

Goethite/Limonite mixture (FeO(OH)·nH2O)

Banded Calcite or Travertine (Calcium Carbonate (CaCO3)) — Sedimentary

Banded Calcite or Travertine

Calcium Carbonate (CaCO3)

Garnet Beads (Garnet Group (complex nesosilicates, e.g., Almandine Fe3Al2(SiO4)3)) — Mineral

Garnet Beads

Garnet Group (complex nesosilicates, e.g., Almandine Fe3Al2(SiO4)3)

Coral Rock (Coquina) (Biogenic Limestone (Calcium Carbonate - CaCO3)) — sedimentary

Coral Rock (Coquina)

Biogenic Limestone (Calcium Carbonate - CaCO3)

Amber with Inclusion (Succiniferous fossil resin (C10H16O)) — mineraloid

Amber with Inclusion

Succiniferous fossil resin (C10H16O)

Granite (Granite (felsic intrusive igneous rock)) — igneous

Granite

Granite (felsic intrusive igneous rock)

Limonite (Iron Ore) (Hydrous Iron Oxide (goethite, lepidocrocite)) — Mineral

Limonite (Iron Ore)

Hydrous Iron Oxide (goethite, lepidocrocite)

Granite (Granite (a common rock type, not a single mineral with a formula. Composed primarily of quartz, feldspar, and mica/amphibole).) — igneous

Granite

Granite (a common rock type, not a single mineral with a formula. Composed primarily of quartz, feldspar, and mica/amphibole).

Granite Cobble/Pebble (Granite) — Igneous

Granite Cobble/Pebble

Granite

Granite (Granite (a plutonic rock)) — Igneous

Granite

Granite (a plutonic rock)

Coquina (Bioclastic Limestone) — sedimentary

Coquina

Bioclastic Limestone

Quartz (Silicon Dioxide (SiO₂)) — Mineral

Quartz

Silicon Dioxide (SiO₂)

Crushed Limestone (Calcium Carbonate (CaCO3)) — Sedimentary

Crushed Limestone

Calcium Carbonate (CaCO3)

BROWN GRANITE (likely 'Tan Brown' or similar) (Granite (specifically a variety rich in orthoclase feldspar, often with biotite and possibly hornblende)) — igneous

BROWN GRANITE (likely 'Tan Brown' or similar)

Granite (specifically a variety rich in orthoclase feldspar, often with biotite and possibly hornblende)

Calligraphy Stone (Mariam Jasper (Fossiliferous Limestone composed of Hematite and Shell remains)) — sedimentary

Calligraphy Stone

Mariam Jasper (Fossiliferous Limestone composed of Hematite and Shell remains)

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

Granite (weathered pebble)

Granite (plutonic igneous rock)

Jade (Jadeite or Nephrite) — Mineral/Mineraloid

Jade

Jadeite or Nephrite

Mineral/Mineraloid

Nephrite Jade (Nephrite) — Mineral/Rock

Nephrite Jade

Nephrite

Chert / Flint (Chert (varieties include Flint)) — Sedimentary

Chert / Flint

Chert (varieties include Flint)

Note on Image Identification: Textile (N/A (Anthropogenic material)) — not a rock

Note on Image Identification: Textile

N/A (Anthropogenic material)

Fossiliferous Limestone (Limestone (composed primarily of calcite with included fossils CaCO3)) — Sedimentary

Fossiliferous Limestone

Limestone (composed primarily of calcite with included fossils CaCO3)

Obsidian (Volcanic glass (SiO2 - Silicon Dioxide with impurities)) — Igneous

Obsidian

Volcanic glass (SiO2 - Silicon Dioxide with impurities)

Gneiss (Gneiss (a type of metamorphic rock)) — Metamorphic Rock

Gneiss

Gneiss (a type of metamorphic rock)

Metamorphic Rock

Pearl (Calcium Carbonate (Aragonite) with Conchiolin; formula: CaCO3) — mineral

Pearl

Calcium Carbonate (Aragonite) with Conchiolin; formula: CaCO3