Rock Identifier

Category

Mineral (Biogenic)

Browse mineral (biogenic) specimens identified by the Rock Identifier community.

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

Cloudy Quartz (or Milky Quartz)

Silicon Dioxide (SiO2)

Black Obsidian (Volcanic Glass (SiO2 + impurities)) — Igneous

Black Obsidian

Volcanic Glass (SiO2 + impurities)

Sapphire (Corundum) (Corundum (Al2O3)) — mineral

Sapphire (Corundum)

Corundum (Al2O3)

Prehnite (Calcium aluminum silicate hydroxide - Ca2Al(AlSi3O10)(OH)2) — mineral

Prehnite

Calcium aluminum silicate hydroxide - Ca2Al(AlSi3O10)(OH)2

Pegmatite (Granitic) with Tourmaline (Granitic Pegmatite (containing Schorl and Quartz)) — igneous

Pegmatite (Granitic) with Tourmaline

Granitic Pegmatite (containing Schorl and Quartz)

Granitic Pegmatite (Pegmatite (composed primarily of Quartz, Feldspar, and Muscovite mica)) — igneous

Granitic Pegmatite

Pegmatite (composed primarily of Quartz, Feldspar, and Muscovite mica)

Schist (Lepidoblastic Mica Schist) — metamorphic

Schist

Lepidoblastic Mica Schist

Porphyry (likely Porphyritic Andesite or Basalt) (Porphyritic Igneous Rock) — igneous

Porphyry (likely Porphyritic Andesite or Basalt)

Porphyritic Igneous Rock

Quartz in Basalt (Xenocryst) (Silicon Dioxide (SiO2) in Mafic Igneous Volcanic Rock) — Igneous

Quartz in Basalt (Xenocryst)

Silicon Dioxide (SiO2) in Mafic Igneous Volcanic Rock

Goldstone (Brown/Gold variety) (Aventurine Glass (SiO2 with Copper inclusions)) — Synthetic/Man-made glass (often mistaken for a mineral)

Goldstone (Brown/Gold variety)

Aventurine Glass (SiO2 with Copper inclusions)

Synthetic/Man-made glass (often mistaken for a mineral)

Basalt with Amygdaloidal Inclusions (Aphanitic Mafic Volcanic Rock (Basalt)) — igneous

Basalt with Amygdaloidal Inclusions

Aphanitic Mafic Volcanic Rock (Basalt)

Banded Iron Formation (BIF) / Tiger Iron variety (Banded Iron Formation (predominantly Hematite, Magnetite, and Chert/Quartz - SiO2 + Fe2O3)) — sedimentary

Banded Iron Formation (BIF) / Tiger Iron variety

Banded Iron Formation (predominantly Hematite, Magnetite, and Chert/Quartz - SiO2 + Fe2O3)

Red Granite (Phaneritic Felsic Igneous Rock (composed of Quartz, Alkali Feldspar, and Plagioclase)) — igneous

Red Granite

Phaneritic Felsic Igneous Rock (composed of Quartz, Alkali Feldspar, and Plagioclase)

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

Giallo Ornamental Granite (Phaneritic Igneous Rock (composed of Quartz, Feldspar, and Mica)) — igneous

Giallo Ornamental Granite

Phaneritic Igneous Rock (composed of Quartz, Feldspar, and Mica)

Granite (Phaneritic Plutonic Felsic Rock (KAlSi3O8 - SiO2 - NaAlSi3O8)) — igneous

Granite

Phaneritic Plutonic Felsic Rock (KAlSi3O8 - SiO2 - NaAlSi3O8)

Granite (Alkali-feldspar rich) (Phaneritic Felsic Igneous Rock (Major components: KAlSi3O8, SiO2)) — igneous

Granite (Alkali-feldspar rich)

Phaneritic Felsic Igneous Rock (Major components: KAlSi3O8, SiO2)

Biotite Gneiss (Gneiss (complex mixture including Biotite K(Mg,Fe)3AlSi3O10(F,OH)2 and Quartz/Feldspar)) — metamorphic

Biotite Gneiss

Gneiss (complex mixture including Biotite K(Mg,Fe)3AlSi3O10(F,OH)2 and Quartz/Feldspar)

Blue Aventurine (Quartzite with Dumortierite inclusions (SiO2)) — metamorphic

Blue Aventurine

Quartzite with Dumortierite inclusions (SiO2)

Amygdaloidal Basalt (Amygdaloidal Basalt) — igneous

Amygdaloidal Basalt

Amygdaloidal Basalt

Sandstone (Arenite (primarily SiO2)) — sedimentary

Sandstone

Arenite (primarily SiO2)

Green Aventurine (Quartzite (variety Aventurine) with Fuchsite inclusions (K(Al,Cr)2(AlSi3O10)(OH)2)) — metamorphic

Green Aventurine

Quartzite (variety Aventurine) with Fuchsite inclusions (K(Al,Cr)2(AlSi3O10)(OH)2)

Granite (Granite (Felsic Plutonic Rock)) — igneous

Granite

Granite (Felsic Plutonic Rock)

Septarian Nodule (Septarian Dragon Stone) (Septarian concretion (composition: Calcite CaCO3, Aragonite CaCO3, and Limestone/Clay)) — sedimentary

Septarian Nodule (Septarian Dragon Stone)

Septarian concretion (composition: Calcite CaCO3, Aragonite CaCO3, and Limestone/Clay)

Chert / Flint (Cryptocrystalline quartz (SiO2)) — Sedimentary

Chert / Flint

Cryptocrystalline quartz (SiO2)

Greenschist (Chlorite schist) — metamorphic

Greenschist

Chlorite schist

Granite (Phaneritic Intrusive Igneous Rock (composed of Quartz, Feldspar, and Mica)) — igneous

Granite

Phaneritic Intrusive Igneous Rock (composed of Quartz, Feldspar, and Mica)

Rutilated Quartz (beads) (SiO2 with TiO2 inclusions (Titanium Dioxide inclusions within Quartz)) — Mineral

Rutilated Quartz (beads)

SiO2 with TiO2 inclusions (Titanium Dioxide inclusions within Quartz)

Sandstone (Quartzite-rich Cobble) (Clastic sedimentary rock (primarily SiO2)) — sedimentary

Sandstone (Quartzite-rich Cobble)

Clastic sedimentary rock (primarily SiO2)

Fossilized Shark Tooth (Fossil Chondrichthyes (various genera such as Carcharias or Odontaspis)) — sedimentary

Fossilized Shark Tooth

Fossil Chondrichthyes (various genera such as Carcharias or Odontaspis)

Granite (Core Sample) (Phaneritic Felsic Igneous Rock (Granite)) — igneous

Granite (Core Sample)

Phaneritic Felsic Igneous Rock (Granite)

Granodiorite (Granodiorite (Quartz + Plagioclase + Alkali Feldspar + Biotite/Hornblende)) — igneous

Granodiorite

Granodiorite (Quartz + Plagioclase + Alkali Feldspar + Biotite/Hornblende)

Basalt (Mafic Volcanic Rock (composed of plagioclase, pyroxene, and olivine)) — igneous

Basalt

Mafic Volcanic Rock (composed of plagioclase, pyroxene, and olivine)

Corundum (Sapphire/Ruby in Matrix) (Corundum (Al2O3)) — mineral

Corundum (Sapphire/Ruby in Matrix)

Corundum (Al2O3)

Diamond (Cluster Ring) (Carbon (C)) — mineral

Diamond (Cluster Ring)

Carbon (C)

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

Milky Quartz (Common Quartz)

Quartz (Silicon Dioxide, SiO2)

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

Rose Quartz

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

Diamond (appearing in jewelry) (Diamond (pure Carbon, C)) — mineral

Diamond (appearing in jewelry)

Diamond (pure Carbon, C)

Diamond (Diamond (pure native carbon, C)) — mineral

Diamond

Diamond (pure native carbon, C)

Rough Diamond (Diamond (C)) — mineral

Rough Diamond

Diamond (C)

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

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Rose Quartz (Pink Quartz (SiO2)) — mineral

Rose Quartz

Pink Quartz (SiO2)