Rock Identifier

Category

Mineraloid (Human Made Geological Specimen)

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

Granite (Granite (Plutonic Igneous Rock)) — igneous

Granite

Granite (Plutonic Igneous Rock)

Tumbled yellow calcite (Calcite (calcium carbonate, CaCO₃)) — mineral

Tumbled yellow calcite

Calcite (calcium carbonate, CaCO₃)

Polished orbicular granite (likely larvikite or gabbroic granite) (Granite-group rock; chiefly feldspar, quartz, and dark pyroxene/amphibole minerals) — igneous

Polished orbicular granite (likely larvikite or gabbroic granite)

Granite-group rock; chiefly feldspar, quartz, and dark pyroxene/amphibole minerals

Banded Chert Arrowhead (Projectile Point) (Microcrystalline Quartz (SiO2)) — sedimentary

Banded Chert Arrowhead (Projectile Point)

Microcrystalline Quartz (SiO2)

Cobalt Blue Glass / Cullet Glass (Silicon dioxide (Amorphous man-made glass)) — mineral

Cobalt Blue Glass / Cullet Glass

Silicon dioxide (Amorphous man-made glass)

Obsidian (Volcanic Glass (70-75% SiO2 with MgO and Fe3O4)) — igneous

Obsidian

Volcanic Glass (70-75% SiO2 with MgO and Fe3O4)

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

Chert (Flint)

Microcrystalline Quartz (SiO2)

Obsidian (Volcanic Glass (Silica / SiO2)) — igneous

Obsidian

Volcanic Glass (Silica / SiO2)

Pearls (Aragonite (calcium carbonate) and Conchiolin) — Mineraloid

Pearls

Aragonite (calcium carbonate) and Conchiolin

Quartzite (Metamorphic Quartzite (SiO2)) — metamorphic

Quartzite

Metamorphic Quartzite (SiO2)

Chert (specifically Tan/Gray Chert) (Microcrystalline quartz (SiO2)) — sedimentary

Chert (specifically Tan/Gray Chert)

Microcrystalline quartz (SiO2)

Aggregate Concrete (Anthropogenic Conglomerate (Technosol)) — sedimentary

Aggregate Concrete

Anthropogenic Conglomerate (Technosol)

Chert (Flint pebble) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (Flint pebble)

Microcrystalline Quartz (SiO2)

Agate (Chalcedony) (Silicon Dioxide (SiO2)) — mineral

Agate (Chalcedony)

Silicon Dioxide (SiO2)

Tumbled pinkish quartz pebble (Quartz, silicon dioxide (SiO₂), likely rose quartz or iron-stained milky quartz) — mineral

Tumbled pinkish quartz pebble

Quartz, silicon dioxide (SiO₂), likely rose quartz or iron-stained milky quartz

Mica Schist (Mica Schist (principally Biotite/Muscovite, Quartz, and Feldspar)) — metamorphic

Mica Schist

Mica Schist (principally Biotite/Muscovite, Quartz, and Feldspar)

Tumbled red jasper (Microcrystalline quartz (chalcedony), primarily SiO₂, colored by iron oxides) — mineral

Tumbled red jasper

Microcrystalline quartz (chalcedony), primarily SiO₂, colored by iron oxides

Milky quartz pebble (Quartz, silicon dioxide (SiO₂)) — mineral

Milky quartz pebble

Quartz, silicon dioxide (SiO₂)

Tumbled granite (Granite, chiefly quartz–feldspar–mica aggregate) — igneous

Tumbled granite

Granite, chiefly quartz–feldspar–mica aggregate

Chert (Jasper and Chalcedony) (Silicon Dioxide (SiO2)) — sedimentary

Chert (Jasper and Chalcedony)

Silicon Dioxide (SiO2)

Flint (Sedimentary cryptocrystalline quartz (SiO2)) — sedimentary

Flint

Sedimentary cryptocrystalline quartz (SiO2)

Mahogany Obsidian (Obsidian (SiO2 + Fe2O3)) — igneous

Mahogany Obsidian

Obsidian (SiO2 + Fe2O3)

Concrete Paver (Artificial Cementitious Rock) (Hydrated Portland Cement Aggregate) — Sedimentary (Synthetic)

Concrete Paver (Artificial Cementitious Rock)

Hydrated Portland Cement Aggregate

Sedimentary (Synthetic)

Polished brecciated jasper or iron-rich agate (Microcrystalline quartz (SiO₂), with hematite/goethite and possible iron oxides) — mineral

Polished brecciated jasper or iron-rich agate

Microcrystalline quartz (SiO₂), with hematite/goethite and possible iron oxides

Likely tumbled yellow-orange mineral or glassy stone (Indeterminate from photograph; possibilities include yellow jasper, calcite, agate, or dyed quartz) — mineral

Likely tumbled yellow-orange mineral or glassy stone

Indeterminate from photograph; possibilities include yellow jasper, calcite, agate, or dyed quartz

Dyed blue-purple tumbled stone, likely quartz or calcite (Uncertain; commonly dyed quartzite/chalcedony (SiO₂) or calcite (CaCO₃)) — mineral

Dyed blue-purple tumbled stone, likely quartz or calcite

Uncertain; commonly dyed quartzite/chalcedony (SiO₂) or calcite (CaCO₃)

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

Chert (Flint)

Microcrystalline Quartz (SiO2)

Blue Goldstone (Man-made glass with cobalt and metal flecks) — man-made glass

Blue Goldstone

Man-made glass with cobalt and metal flecks

Tumbled pale chalcedony (likely quartz) (Microcrystalline quartz, SiO₂; possibly pale agate or quartz) — mineral

Tumbled pale chalcedony (likely quartz)

Microcrystalline quartz, SiO₂; possibly pale agate or quartz

Rainbow Hematite Ring (Iron(III) oxide (Fe2O3) with thin-film coating) — mineral

Rainbow Hematite Ring

Iron(III) oxide (Fe2O3) with thin-film coating

Painted Rock (Weathered Sedimentary Rock (Painted)) — sedimentary

Painted Rock

Weathered Sedimentary Rock (Painted)

Purple Dyed Dalmatian Stone (Dyed Peralkaline Trachyte) — igneous

Purple Dyed Dalmatian Stone

Dyed Peralkaline Trachyte

Colorless faceted gemstones, likely quartz (rock crystal) (Quartz, silicon dioxide (SiO₂), trigonal crystal system) — gemstone

Colorless faceted gemstones, likely quartz (rock crystal)

Quartz, silicon dioxide (SiO₂), trigonal crystal system

Amber (Succinite (Organic Mineraloid)) — mineral

Amber

Succinite (Organic Mineraloid)

Precious Opal (Hydrated Silica (SiO2·nH2O)) — mineral

Precious Opal

Hydrated Silica (SiO2·nH2O)

Polished brown chalcedony (likely carnelian or jasper) (Microcrystalline quartz, SiO₂; iron oxides produce the brown coloration) — mineral

Polished brown chalcedony (likely carnelian or jasper)

Microcrystalline quartz, SiO₂; iron oxides produce the brown coloration

Chert (Arrowhead Fragment) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (Arrowhead Fragment)

Microcrystalline Quartz (SiO2)

Red Slag Glass (Amorphous Silica (Industrial byproduct with metallic oxide dopants)) — Mineraloid / Industrial Byproduct

Red Slag Glass

Amorphous Silica (Industrial byproduct with metallic oxide dopants)

Mineraloid / Industrial Byproduct

Fossilized gastropod (likely nerite or related sea snail) (Gastropoda; shell composed originally of aragonite/calcite, commonly replaced or infilled by calcite) — fossil

Fossilized gastropod (likely nerite or related sea snail)

Gastropoda; shell composed originally of aragonite/calcite, commonly replaced or infilled by calcite

Slag (Industrial Byproduct) (Artificial silicate/iron byproduct) — Mineral description (Anthropogenic material)

Slag (Industrial Byproduct)

Artificial silicate/iron byproduct

Mineral description (Anthropogenic material)

Tumbled dark stone, possibly hematite or black jasper (Uncertain; likely hematite (Fe₂O₃) or fine-grained chalcedony/jasper (SiO₂)) — mineral

Tumbled dark stone, possibly hematite or black jasper

Uncertain; likely hematite (Fe₂O₃) or fine-grained chalcedony/jasper (SiO₂)

Tumbled milky quartz (likely) (Quartz, silicon dioxide (SiO₂)) — mineral

Tumbled milky quartz (likely)

Quartz, silicon dioxide (SiO₂)