Rock Identifier

Category

Igneous Rock

Browse igneous rock specimens identified by the Rock Identifier community.

Peridot (Olivine) (Olivine, (Mg,Fe)2SiO4) — Mineral

Peridot (Olivine)

Olivine, (Mg,Fe)2SiO4

Amethyst (SiO2 (Silicon Dioxide) - a variety of Quartz) — Mineral

Amethyst

SiO2 (Silicon Dioxide) - a variety of Quartz

Shale (sub-type: Carbonaceous Shale) (Lutaceous Sedimentary Rock) — sedimentary

Shale (sub-type: Carbonaceous Shale)

Lutaceous Sedimentary Rock

Quartzite (Quartzite (primarily composed of SiO

O₂)) — Sedimentary Rock

Quartzite

Quartzite (primarily composed of SiO O₂)

Sedimentary Rock

Painted River Rock (Anthropogenic-modified Siliciclastic Sedimentary Rock) — Sedimentary

Painted River Rock

Anthropogenic-modified Siliciclastic Sedimentary Rock

Smoky Quartz (SiO2 (Silicon Dioxide)) — Mineral

Smoky Quartz

SiO2 (Silicon Dioxide)

River Rock (Glacial Cobbles) (Fluvial Alluvium (Mixed lithology including Quartzite, Basalt, and Granite)) — Mixed (predominantly sedimentary and igneous)

River Rock (Glacial Cobbles)

Fluvial Alluvium (Mixed lithology including Quartzite, Basalt, and Granite)

Mixed (predominantly sedimentary and igneous)

Unakite (Epidotized Granite (Composed of Orthoclase Feldspar, Epidote, and Quartz)) — metamorphic

Unakite

Epidotized Granite (Composed of Orthoclase Feldspar, Epidote, and Quartz)

Crushed Limestone (Calcium Carbonate (CaCO3)) — Sedimentary

Crushed Limestone

Calcium Carbonate (CaCO3)

Sodalite (Sodalite - Sodium Aluminum Silicate Chloride (Na8(Al6Si6O24)Cl2)) — mineral

Sodalite

Sodalite - Sodium Aluminum Silicate Chloride (Na8(Al6Si6O24)Cl2)

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

Quartz (Milky/Common Quartz)

Silicon Dioxide (SiO2)

Rose Quartz (Silicon Dioxide (SiO2)) — mineral

Rose Quartz

Silicon Dioxide (SiO2)

Rose Quartz (Silicon Dioxide (SiO2) with traces of Titanium, Iron, or Manganese) — mineral

Rose Quartz

Silicon Dioxide (SiO2) with traces of Titanium, Iron, or Manganese

Banded Sandstone (Arenite with Liesegang banding) — sedimentary

Banded Sandstone

Arenite with Liesegang banding

Agate Geode Slice (with Druzy Quartz) (Silicon Dioxide (SiO2)) — mineral

Agate Geode Slice (with Druzy Quartz)

Silicon Dioxide (SiO2)

Turquoise (Hydrated phosphate of copper and aluminium [CuAl6(PO4)4(OH)8·4H2O]) — mineral

Turquoise

Hydrated phosphate of copper and aluminium [CuAl6(PO4)4(OH)8·4H2O]

Red Garnet (likely Almandine or Pyrope) (Garnet group: X3Y2(SiO4)3 (e.g., Almandine: Fe3Al2Si3O12)) — mineral

Red Garnet (likely Almandine or Pyrope)

Garnet group: X3Y2(SiO4)3 (e.g., Almandine: Fe3Al2Si3O12)

Sandstone or Siltstone (Arenite (if sandstone)) — Sedimentary

Sandstone or Siltstone

Arenite (if sandstone)

Druzy Quartz on Limestone (Silicon Dioxide (SiO2)) — mineral

Druzy Quartz on Limestone

Silicon Dioxide (SiO2)

Chert (Quartzite-rich River Pebble) (Silicon Dioxide (SiO2)) — sedimentary

Chert (Quartzite-rich River Pebble)

Silicon Dioxide (SiO2)

Quartz (Silicon dioxide (SiO2)) — mineral

Quartz

Silicon dioxide (SiO2)

Amazonite (KAlSi3O8 (Potassium Feldspar, variety of Microcline)) — Mineral

Amazonite

KAlSi3O8 (Potassium Feldspar, variety of Microcline)

Amethyst (Quartz) (SiO2 (Silicon Dioxide)) — mineral

Amethyst (Quartz)

SiO2 (Silicon Dioxide)

Unakite (Epidote-Feldspar rock) — Metamorphic Rock

Unakite

Epidote-Feldspar rock

Metamorphic Rock

Quartz Geode (Silicon Dioxide (SiO2) in Geode form) — sedimentary

Quartz Geode

Silicon Dioxide (SiO2) in Geode form

Sandstone with Concretions / Liesegang Rings (Arenite with iron oxide banding) — sedimentary

Sandstone with Concretions / Liesegang Rings

Arenite with iron oxide banding

Tiger's Eye (Mineral Collection) (Tiger's Eye (SiO2 with crocidolite inclusions)) — mineral

Tiger's Eye (Mineral Collection)

Tiger's Eye (SiO2 with crocidolite inclusions)

Quartz (Quartz (SiO2 - Silicon Dioxide)) — Mineral

Quartz

Quartz (SiO2 - Silicon Dioxide)

Biotite Schist (Biotite Schist) — Metamorphic

Biotite Schist

Biotite Schist

Quartz (River Pebble) (Silicon Dioxide (SiO2)) — mineral

Quartz (River Pebble)

Silicon Dioxide (SiO2)

Clear Quartz Crystal (Herkimer Diamond style) (Silicon Dioxide (SiO2)) — mineral

Clear Quartz Crystal (Herkimer Diamond style)

Silicon Dioxide (SiO2)

Sandstone (with Iron concretions/staining) (Arenite (composed primarily of Quartz and Feldspar with Iron Oxide cement)) — sedimentary

Sandstone (with Iron concretions/staining)

Arenite (composed primarily of Quartz and Feldspar with Iron Oxide cement)

Sandstone (likely Quartzose Sandstone) (Arenite (SiO2 based)) — sedimentary

Sandstone (likely Quartzose Sandstone)

Arenite (SiO2 based)

Olivine (Peridot) (Magnesium Iron Silicate (Mg,Fe)2SiO4) — mineral

Olivine (Peridot)

Magnesium Iron Silicate (Mg,Fe)2SiO4

Magnetite Sand (Black Sand) (Magnetite (Fe3O4)) — mineral

Magnetite Sand (Black Sand)

Magnetite (Fe3O4)

Serpentinite (Serpentinite (a rock composed predominantly of serpentine group minerals)) — metamorphic

Serpentinite

Serpentinite (a rock composed predominantly of serpentine group minerals)

Chert (Yellow Jasper/Quartzite Pebble) (Microcrystalline Silicon Dioxide (SiO2)) — sedimentary

Chert (Yellow Jasper/Quartzite Pebble)

Microcrystalline Silicon Dioxide (SiO2)

Quartzite Cobble (Quartzite (primarily SiO2)) — metamorphic

Quartzite Cobble

Quartzite (primarily SiO2)

Biotite or Phlogopite Mica (K(Mg,Fe)3(AlSi3O10)(F,OH)2) — mineral

Biotite or Phlogopite Mica

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

Sandstone (Ferruginous) (Arenite (primarily SiO2 with iron oxide cement)) — sedimentary

Sandstone (Ferruginous)

Arenite (primarily SiO2 with iron oxide cement)

Quartzite (Water-worn Cobble) (Quartzite (Composition: 90%+ SiO2)) — metamorphic

Quartzite (Water-worn Cobble)

Quartzite (Composition: 90%+ SiO2)

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

Sandstone (River Rock)

Arenite (composed primarily of SiO2)