Rock Identifier

Category

Mineraloid (Human Made Geological Specimen)

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

Red Sandstone (Arenite (Ferruginous Sandstone)) — sedimentary

Red Sandstone

Arenite (Ferruginous Sandstone)

Massive Quartz (Yellow/Citrine variety) (Silicon Dioxide (SiO2)) — mineral

Massive Quartz (Yellow/Citrine variety)

Silicon Dioxide (SiO2)

Quartzite (Quartzite (primarily SiO2)) — metamorphic

Quartzite

Quartzite (primarily SiO2)

Quartzite Pebble (Quartzite (primarily SiO2)) — metamorphic

Quartzite Pebble

Quartzite (primarily SiO2)

Desert Rose (Gypsum (variety Selenite) or Barite, CaSO4·2H2O) — mineral

Desert Rose

Gypsum (variety Selenite) or Barite, CaSO4·2H2O

Iron-rich sandstone or laterite (Ferruginous sandstone; mainly quartz (SiO₂) cemented or stained by iron oxides such as hematite (Fe₂O₃) and goethite (FeO(OH))) — sedimentary

Iron-rich sandstone or laterite

Ferruginous sandstone; mainly quartz (SiO₂) cemented or stained by iron oxides such as hematite (Fe₂O₃) and goethite (FeO(OH))

Honey Calcite (Calcium Carbonate (CaCO3)) — mineral

Honey Calcite

Calcium Carbonate (CaCO3)

Granite (Granite (composed primarily of Quartz SiO₂, Alkali Feldspar KAlSi₃O–NaAlSi₃O–CaAl₂Si₂O₈, and Plagioclase Feldspar)) — igneous

Granite

Granite (composed primarily of Quartz SiO₂, Alkali Feldspar KAlSi₃O–NaAlSi₃O–CaAl₂Si₂O₈, and Plagioclase Feldspar)

Dendritic Agate (Silicon Dioxide with Manganese/Iron oxide inclusions (SiO2)) — Mineral

Dendritic Agate

Silicon Dioxide with Manganese/Iron oxide inclusions (SiO2)

Likely dark green-gray metamorphic pebble (Indeterminate; possibly chlorite schist, serpentinite, or amphibolite) — metamorphic

Likely dark green-gray metamorphic pebble

Indeterminate; possibly chlorite schist, serpentinite, or amphibolite

Fossil bivalve shell (Fossilized or partially mineralized bivalve; exact genus cannot be determined from the image) — fossil

Fossil bivalve shell

Fossilized or partially mineralized bivalve; exact genus cannot be determined from the image

Pyrite (on Quartz matrix) (Iron Disulfide (FeS2)) — mineral

Pyrite (on Quartz matrix)

Iron Disulfide (FeS2)

Pyrite (Fool's Gold) (Iron Disulfide (FeS2)) — mineral

Pyrite (Fool's Gold)

Iron Disulfide (FeS2)

Calcite (likely a tumbled specimen) (Calcite (CaCO
3
)) — Mineral

Calcite (likely a tumbled specimen)

Calcite (CaCO 3 )

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

Sandstone

Arenite (composed primarily of SiO2)

Natural Pearl (appearing in a jewelry setting) (Calcium Carbonate (mostly Aragonite), CaCO3 with Conchiolin) — mineral

Natural Pearl (appearing in a jewelry setting)

Calcium Carbonate (mostly Aragonite), CaCO3 with Conchiolin

Sandstone (Arenite (SiO2 based)) — sedimentary

Sandstone

Arenite (SiO2 based)

Citrine (Iron-stained Quartz) (Silicon Dioxide (SiO2)) — mineral

Citrine (Iron-stained Quartz)

Silicon Dioxide (SiO2)

Milky Quartz (Tumbled/Water-worn) (Silicon Dioxide (SiO2)) — mineral

Milky Quartz (Tumbled/Water-worn)

Silicon Dioxide (SiO2)

Quartz Druse (on Chalcedony/Agate base) (Silicon Dioxide (SiO2)) — mineral

Quartz Druse (on Chalcedony/Agate base)

Silicon Dioxide (SiO2)

Mixed Mineral and Fossil Collection (Multi-specimen assemblage (SiO2, CaCO3, FeS2, etc.)) — mineral

Mixed Mineral and Fossil Collection

Multi-specimen assemblage (SiO2, CaCO3, FeS2, etc.)

Milky quartz-rich rock (Quartz (SiO₂), likely massive milky quartz with minor iron-oxide staining and attached host material) — mineral

Milky quartz-rich rock

Quartz (SiO₂), likely massive milky quartz with minor iron-oxide staining and attached host material

Chert / Flint (Cryptocrystalline Quartz (Silicon Dioxide, SiO2)) — sedimentary

Chert / Flint

Cryptocrystalline Quartz (Silicon Dioxide, SiO2)

Yellow Calcite (Calcium Carbonate (CaCO3)) — mineral

Yellow Calcite

Calcium Carbonate (CaCO3)

Clear Quartz Cluster (Silicon Dioxide (SiO2)) — mineral

Clear Quartz Cluster

Silicon Dioxide (SiO2)

Quartz-rich granite or pegmatitic rock (Granite/pegmatite; chiefly quartz (SiO₂), feldspar, and minor mica) — igneous

Quartz-rich granite or pegmatitic rock

Granite/pegmatite; chiefly quartz (SiO₂), feldspar, and minor mica

Pyrite (Fool's Gold) (Iron Disulfide (FeS2)) — mineral

Pyrite (Fool's Gold)

Iron Disulfide (FeS2)

Charoite (Charoite (K(Ca,Na)2Si4O10(OH,F)·H2O)) — metamorphic

Charoite

Charoite (K(Ca,Na)2Si4O10(OH,F)·H2O)

Diamond (Cut Specimen) (Carbon (C)) — mineral

Diamond (Cut Specimen)

Carbon (C)

Iron Meteorite (Siderite (Iron-Nickel Alloy)) — meteorite

Iron Meteorite

Siderite (Iron-Nickel Alloy)

Chert (Brown Variety) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (Brown Variety)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert Nodules (Chert (Silicon Dioxide, SiO2)) — sedimentary

Chert Nodules

Chert (Silicon Dioxide, SiO2)

Chert (Jasper/Agate variety) (Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (Jasper/Agate variety)

Cryptocrystalline Quartz (SiO2)

Rounded gray-brown river cobble (Indeterminate lithology; possibly weathered quartzite, chert, or fine-grained sandstone) — sedimentary

Rounded gray-brown river cobble

Indeterminate lithology; possibly weathered quartzite, chert, or fine-grained sandstone

Milky Quartz (Silicon Dioxide (SiO2)) — mineral

Milky Quartz

Silicon Dioxide (SiO2)

Dendritic Agate (Tumbled) (Silicon Dioxide (SiO2) with inclusions) — mineral

Dendritic Agate (Tumbled)

Silicon Dioxide (SiO2) with inclusions

Red Jasper (Silicon Dioxide (SiO2) with Iron Oxide inclusions) — sedimentary

Red Jasper

Silicon Dioxide (SiO2) with Iron Oxide inclusions

Fossiliferous limestone, possibly an oyster or other bivalve fossil (Calcite (CaCO₃) shell material preserved in micritic limestone; exact fossil taxon cannot be confirmed from one image) — fossil

Fossiliferous limestone, possibly an oyster or other bivalve fossil

Calcite (CaCO₃) shell material preserved in micritic limestone; exact fossil taxon cannot be confirmed from one image

Quartz (Milky or Cloudy Quartz) (Quartz (Silicon Dioxide, SiO2)) — mineral

Quartz (Milky or Cloudy Quartz)

Quartz (Silicon Dioxide, SiO2)

Greenstone / Basalt with Amygdule (Amygdaloidal Basalt (altered to Greenstone)) — igneous

Greenstone / Basalt with Amygdule

Amygdaloidal Basalt (altered to Greenstone)

Limonite (Ironstone Concretion) (Limonite (Hydrous Ferric Oxides mixed with Goethite)) — sedimentary

Limonite (Ironstone Concretion)

Limonite (Hydrous Ferric Oxides mixed with Goethite)

Chert (Septarian Nodules / Weathered Silex) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (Septarian Nodules / Weathered Silex)

Microcrystalline Quartz (SiO2)