Rock Identifier

Category

Organic Crystal (Mineraloid)

Browse organic crystal (mineraloid) specimens identified by the Rock Identifier community.

Gabbro (Gabbro (composed mainly of calcium-rich plagioclase feldspar and pyroxene)) — igneous

Gabbro

Gabbro (composed mainly of calcium-rich plagioclase feldspar and pyroxene)

Pegmatite (Igneous Pegmatite) — igneous

Pegmatite

Igneous Pegmatite

Granite (Felsic intrusive igneous rock) — igneous

Granite

Felsic intrusive igneous rock

Granite (Phaneritic plutonic rock (Quartz, Feldspar, Mica)) — igneous

Granite

Phaneritic plutonic rock (Quartz, Feldspar, Mica)

Granite (Felsic intrusive igneous rock) — igneous

Granite

Felsic intrusive igneous rock

Granite (Intrusive Igneous Rock) — igneous

Granite

Intrusive Igneous Rock

Quartzite (Metamorphic Quartzite) — metamorphic

Quartzite

Metamorphic Quartzite

Greenstone (Metamorphic mafic rock (greenschist facies)) — metamorphic

Greenstone

Metamorphic mafic rock (greenschist facies)

Greenstone / Metagraywacke (Metamorphosed basaltic or sedimentary rock (Complex Silicate)) — metamorphic

Greenstone / Metagraywacke

Metamorphosed basaltic or sedimentary rock (Complex Silicate)

Diorite (Intermediate Phaneritic Igneous Rock (Diorite)) — igneous

Diorite

Intermediate Phaneritic Igneous Rock (Diorite)

Granite (Intrusive Igneous Rock) — igneous

Granite

Intrusive Igneous Rock

Granite (Granite (Phaneritic igneous rock)) — igneous

Granite

Granite (Phaneritic igneous rock)

Tumbled Slate or Basalt Pebble (Metamorphic fine-grained rock / Slate or Phyllite) — metamorphic

Tumbled Slate or Basalt Pebble

Metamorphic fine-grained rock / Slate or Phyllite

Pearl (likely Freshwater or Akoya Cultured) (Aragonite / Conchiolin composite (CaCO3)) — Mineralloid (Organic gemstone)

Pearl (likely Freshwater or Akoya Cultured)

Aragonite / Conchiolin composite (CaCO3)

Mineralloid (Organic gemstone)

Granite (Intrusive igneous rock) — igneous

Granite

Intrusive igneous rock

Granite (Granite (composed primarily of Quartz SiO2, Potassium Feldspar KAlSi3O8, and Plagioclase)) — Igneous

Granite

Granite (composed primarily of Quartz SiO2, Potassium Feldspar KAlSi3O8, and Plagioclase)

Rose Quartz (Silicon Dioxide (SiO2) with trace amounts of titanium, iron, or manganese) — mineral

Rose Quartz

Silicon Dioxide (SiO2) with trace amounts of titanium, iron, or manganese

Tumbled azurite–malachite or blue jasper (tentative) (Likely azurite-bearing copper mineral aggregate; composition commonly Cu₃(CO₃)₂(OH)₂ with associated malachite Cu₂CO₃(OH)₂) — mineral

Tumbled azurite–malachite or blue jasper (tentative)

Likely azurite-bearing copper mineral aggregate; composition commonly Cu₃(CO₃)₂(OH)₂ with associated malachite Cu₂CO₃(OH)₂

Prasiolite and Quartz Crystal Cluster (Quartz (SiO2); Prasiolite is a variety of Quartz) — mineral

Prasiolite and Quartz Crystal Cluster

Quartz (SiO2); Prasiolite is a variety of Quartz

Granite (Felsic intrusive igneous rock) — igneous

Granite

Felsic intrusive igneous rock

Granite (Intrusive igneous rock composed mainly of quartz, alkali feldspar, and plagioclase) — igneous

Granite

Intrusive igneous rock composed mainly of quartz, alkali feldspar, and plagioclase

Weathered porphyritic volcanic rock (Likely andesite or dacite, with feldspar phenocrysts in a fine-grained groundmass) — igneous

Weathered porphyritic volcanic rock

Likely andesite or dacite, with feldspar phenocrysts in a fine-grained groundmass

Sandstone (Quartzose Sandstone) (Arenite (primarily SiO2 with minor Fe2O3)) — sedimentary

Sandstone (Quartzose Sandstone)

Arenite (primarily SiO2 with minor Fe2O3)

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

Opal

Hydrated Silica (SiO2·nH2O)

Granite (Intrusive Igneous Rock) — igneous

Granite

Intrusive Igneous Rock

Schist (Mica Schist) — metamorphic

Schist

Mica Schist

Black Opal Ring (Carved Opal) (Hydrated Silicon Dioxide (SiO2·nH2O)) — gemstone

Black Opal Ring (Carved Opal)

Hydrated Silicon Dioxide (SiO2·nH2O)

Black Opal (Triplet) (Hydrated Silica (SiO2·nH2O)) — mineral

Black Opal (Triplet)

Hydrated Silica (SiO2·nH2O)

Mahogany Obsidian (Volcanic Glass with Hematite inclusions (SiO2 + Fe2O3)) — igneous

Mahogany Obsidian

Volcanic Glass with Hematite inclusions (SiO2 + Fe2O3)

Anthracite Coal (Anthracite (Carbon-rich mineraloid)) — metamorphic

Anthracite Coal

Anthracite (Carbon-rich mineraloid)

Opal (in Jewelry Setting) (Hydrated Silicon Dioxide (SiO2·nH2O)) — gemstone

Opal (in Jewelry Setting)

Hydrated Silicon Dioxide (SiO2·nH2O)

Mahogany Obsidian (Volcanic Glass with Hematite inclusions) — igneous

Mahogany Obsidian

Volcanic Glass with Hematite inclusions

Amber (Succinates) — mineraloid

Amber

Succinates

Cobalt Glass Slug (Man-made Glass) (Amorphous Silica with Cobalt Oxide (SiO2 + CoO)) — mineraloid

Cobalt Glass Slug (Man-made Glass)

Amorphous Silica with Cobalt Oxide (SiO2 + CoO)

Cullet Glass (Slag Glass) (Amorphous Silicon Dioxide (Industrial Man-made)) — mineraloid

Cullet Glass (Slag Glass)

Amorphous Silicon Dioxide (Industrial Man-made)

Mahogany Obsidian (Obsidian (Volcanic Glass with Hematite/Magnetite inclusions), SiO2) — igneous

Mahogany Obsidian

Obsidian (Volcanic Glass with Hematite/Magnetite inclusions), SiO2

Fulgurite (Fulgurite (Lechatelierite-rich fused silica)) — mineraloid

Fulgurite

Fulgurite (Lechatelierite-rich fused silica)

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

Precious Opal

Hydrated Silica (SiO2·nH2O)

Amber (Succinates (C10H16O)) — mineraloid

Amber

Succinates (C10H16O)

Tektite (Indochinite) (Tektite - High-silica amorphous glass (SiO2 + Al2O3)) — mineraloid

Tektite (Indochinite)

Tektite - High-silica amorphous glass (SiO2 + Al2O3)

Tektite (Tektite (high-silica natural glass)) — Mineraloid

Tektite

Tektite (high-silica natural glass)

Leland Blue Stone (Anthropogenic Iron Smelting Slag) — mineraloid

Leland Blue Stone

Anthropogenic Iron Smelting Slag