Rock Identifier

Category

Mineraloid (Human Made Geological Specimen)

Browse mineraloid (human made geological specimen) specimens identified by the Rock Identifier community.

Quartz (Smoky/Milky variety with inclusion) (Silicon Dioxide (SiO2)) — mineral

Quartz (Smoky/Milky variety with inclusion)

Silicon Dioxide (SiO2)

Obsidian (Volcanic Glass (SiO2, usually 70% or more)) — igneous

Obsidian

Volcanic Glass (SiO2, usually 70% or more)

Pyrite (Iron Sulfide (FeS2)) — mineral

Pyrite

Iron Sulfide (FeS2)

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

Milky Quartz Pebbles

Silicon Dioxide (SiO2)

Beach Pebble (likely Quartz or Chalcedony) (Silicon Dioxide (SiO2)) — Mineral

Beach Pebble (likely Quartz or Chalcedony)

Silicon Dioxide (SiO2)

Quartz (Smoky/Milky variety with matrix) (Silicon Dioxide (SiO2)) — mineral

Quartz (Smoky/Milky variety with matrix)

Silicon Dioxide (SiO2)

Snowflake Obsidian (Volcanic Glass (SiO2 + impurities)) — igneous

Snowflake Obsidian

Volcanic Glass (SiO2 + impurities)

Sodalite (Sodalite (Na8(Al6Si6O24)Cl2)) — mineral

Sodalite

Sodalite (Na8(Al6Si6O24)Cl2)

Fossil Shell (Bivalve) (Phylum Mollusca, Class Bivalvia (typically composed of Calcium Carbonate / CaCO3)) — sedimentary

Fossil Shell (Bivalve)

Phylum Mollusca, Class Bivalvia (typically composed of Calcium Carbonate / CaCO3)

Ferruginous Quartz (Iron-stained Quartz) (Silicon Dioxide with Iron Oxide (SiO2 + Fe2O3)) — mineral

Ferruginous Quartz (Iron-stained Quartz)

Silicon Dioxide with Iron Oxide (SiO2 + Fe2O3)

Blue Quartz (Quartz (SiO2) with inclusions) — Mineral

Blue Quartz

Quartz (SiO2) with inclusions

Sand Dollar Fossil (Echinoidea (Clypeasteroida)) — sedimentary

Sand Dollar Fossil

Echinoidea (Clypeasteroida)

Red Granite (Phaneritic Plutonic Rock (High Potassium Feldspar)) — igneous

Red Granite

Phaneritic Plutonic Rock (High Potassium Feldspar)

Amygdaloidal Basalt (Amygdaloidal Basalt (Mafic volcanic rock)) — igneous

Amygdaloidal Basalt

Amygdaloidal Basalt (Mafic volcanic rock)

Sandstone (Ferruginous) (Arenite (primarily SiO2 with Fe2O3/FeO(OH) cementing agents)) — sedimentary

Sandstone (Ferruginous)

Arenite (primarily SiO2 with Fe2O3/FeO(OH) cementing agents)

Chert (Cherty Shale / Flint) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (Cherty Shale / Flint)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Pumice (Pumice (Vesicular volcanic glass / Rhyolite or Trachyte)) — igneous

Pumice

Pumice (Vesicular volcanic glass / Rhyolite or Trachyte)

Quartzite (Quartzite (SiO2)) — metamorphic

Quartzite

Quartzite (SiO2)

Fossilized Brachiopod (Phylum Brachiopoda (replaced by Calcite/CaCO3)) — sedimentary

Fossilized Brachiopod

Phylum Brachiopoda (replaced by Calcite/CaCO3)

Zebra Jasper (Silicon Dioxide (SiO2) - Macro-crystalline Quartz/Chert with impurities) — sedimentary

Zebra Jasper

Silicon Dioxide (SiO2) - Macro-crystalline Quartz/Chert with impurities

Quartz Geode (Silicon Dioxide (SiO2) within a geode) — mineral

Quartz Geode

Silicon Dioxide (SiO2) within a geode

Amethyst (Silicon Dioxide (SiO2) with iron impurities) — mineral

Amethyst

Silicon Dioxide (SiO2) with iron impurities

Peridot in Basalt/Xenolith (Olivine (Mg, Fe)2SiO4 in Vesicular Basalt) — igneous

Peridot in Basalt/Xenolith

Olivine (Mg, Fe)2SiO4 in Vesicular Basalt

Pink Granite (Alkali Feldspar Granite) (Phaneritic Felsic Igneous Rock (composed primarily of KAlSi3O8, SiO2, and NaAlSi3O8)) — igneous

Pink Granite (Alkali Feldspar Granite)

Phaneritic Felsic Igneous Rock (composed primarily of KAlSi3O8, SiO2, and NaAlSi3O8)

Staurolite (Fairy Stone) (Staurolite (formula: Fe2+2Al9Si4O23(OH))) — metamorphic

Staurolite (Fairy Stone)

Staurolite (formula: Fe2+2Al9Si4O23(OH))

Graphite-veined Quartzite (Meta-sedimentary Quartzite with Carbonaceous/Graphitic Inclusions (SiO2 + C)) — metamorphic

Graphite-veined Quartzite

Meta-sedimentary Quartzite with Carbonaceous/Graphitic Inclusions (SiO2 + C)

Basalt (Basalt (Mafic volcanic rock)) — igneous

Basalt

Basalt (Mafic volcanic rock)

Ruby (Corundum (Al2O3 with Chromium impurities)) — mineral

Ruby

Corundum (Al2O3 with Chromium impurities)

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

Sandstone (Flagstone)

Arenite (composed primarily of SiO2)

Snowflake Obsidian (Vitreous volcanic silicate (SiO2 with Cristobalite inclusions)) — Igneous

Snowflake Obsidian

Vitreous volcanic silicate (SiO2 with Cristobalite inclusions)

Fossil Shell (Bivalve) (Class Bivalvia (Likely a member of the Ostreidae or Gryphaeidae family), CaCO3) — sedimentary

Fossil Shell (Bivalve)

Class Bivalvia (Likely a member of the Ostreidae or Gryphaeidae family), CaCO3

Quartz Pebble (Silicon Dioxide (SiO2)) — mineral

Quartz Pebble

Silicon Dioxide (SiO2)

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

Black Obsidian

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

Mixed Quartz and Jasper Pebbles (Silicon Dioxide (SiO2)) — Mineral

Mixed Quartz and Jasper Pebbles

Silicon Dioxide (SiO2)

Milky Quartz (with Iron staining) (Silicon Dioxide (SiO2)) — mineral

Milky Quartz (with Iron staining)

Silicon Dioxide (SiO2)

Milky Quartz (Silicon Dioxide (SiO2)) — mineral

Milky Quartz

Silicon Dioxide (SiO2)

Green Aventurine (Silicon Dioxide (SiO2) with Fuchsite inclusions) — metamorphic

Green Aventurine

Silicon Dioxide (SiO2) with Fuchsite inclusions

Rhodonite (Manganese Silicate (Mn, Fe, Mg, Ca)SiO3) — mineral

Rhodonite

Manganese Silicate (Mn, Fe, Mg, Ca)SiO3

Mica Schist (Muscovite/Biotite Schist) — metamorphic

Mica Schist

Muscovite/Biotite Schist

Shale (possibly) (Shale (fine-grained clastic sedimentary rock)) — sedimentary

Shale (possibly)

Shale (fine-grained clastic sedimentary rock)

Sandstone (Ferruginous) (Arenite (with Iron Oxide cement)) — sedimentary

Sandstone (Ferruginous)

Arenite (with Iron Oxide cement)

Basalt (Basalt (comprising plagioclase, pyroxene, and olivine)) — igneous

Basalt

Basalt (comprising plagioclase, pyroxene, and olivine)