Rock Identifier

Category

Mineraloid (Human Made Geological Specimen)

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

Graphic Granite (Graphic Granite (Granitic Pegmatite), typically KAlSi3O8 (Feldspar) + SiO2 (Quartz)) — igneous

Graphic Granite

Graphic Granite (Granitic Pegmatite), typically KAlSi3O8 (Feldspar) + SiO2 (Quartz)

Sandstone (Ferruginous) (Arenite (composed primarily of SiO2 with Fe2O3 cement)) — sedimentary

Sandstone (Ferruginous)

Arenite (composed primarily of SiO2 with Fe2O3 cement)

Coral Fossil (Hexagonaria) (Hexagonaria sp. (Silica-replaced)) — fossil

Coral Fossil (Hexagonaria)

Hexagonaria sp. (Silica-replaced)

Quartz (Chert/Chalcedony variety) (Silicon Dioxide (SiO2)) — mineral

Quartz (Chert/Chalcedony variety)

Silicon Dioxide (SiO2)

Petrified Wood (Silicified wood (primarily SiO2)) — fossil

Petrified Wood

Silicified wood (primarily SiO2)

Quartz with impurities or Host Rock (SiO2 (Silicon Dioxide) with mixed silicates) — mineral

Quartz with impurities or Host Rock

SiO2 (Silicon Dioxide) with mixed silicates

Sulfur-bearing Limestone (Solfatara Specimen) (Sulfur-rich Bio-limestone (Calcium Carbonate with Native Sulfur, S8)) — sedimentary

Sulfur-bearing Limestone (Solfatara Specimen)

Sulfur-rich Bio-limestone (Calcium Carbonate with Native Sulfur, S8)

Limonite-stained Granite (Felsic Plutonic Rock with Hydrated Iron Oxides) — igneous

Limonite-stained Granite

Felsic Plutonic Rock with Hydrated Iron Oxides

Quartz (Silicon Dioxide (SiO2)) — mineral

Quartz

Silicon Dioxide (SiO2)

Chert (Jasper variety) (Silicon Dioxide (SiO2)) — sedimentary

Chert (Jasper variety)

Silicon Dioxide (SiO2)

Silicon Carbide (Carborundum) (Silicon Carbide (SiC) / Moissanite (natural)) — mineral

Silicon Carbide (Carborundum)

Silicon Carbide (SiC) / Moissanite (natural)

Quartz with Basalt inclusion (Silicon Dioxide (SiO2) with mafic silicate rock) — igneous and sedimentary/metamorphic mix

Quartz with Basalt inclusion

Silicon Dioxide (SiO2) with mafic silicate rock

igneous and sedimentary/metamorphic mix

Milky Quartz (Silicon Dioxide (SiO2)) — mineral

Milky Quartz

Silicon Dioxide (SiO2)

Red Sandstone Pebble (Sedimentary quartz sandstone) — sedimentary

Red Sandstone Pebble

Sedimentary quartz sandstone

Quartz (Iron-Stained / Yellow Quartz) (Silicon Dioxide (SiO2)) — mineral

Quartz (Iron-Stained / Yellow Quartz)

Silicon Dioxide (SiO2)

Pyrite in Matrix (Iron Sulfide (FeS2)) — mineral

Pyrite in Matrix

Iron Sulfide (FeS2)

Gray Chalcedony Gemstone (Chalcedony (SiO2)) — mineral

Gray Chalcedony Gemstone

Chalcedony (SiO2)

Chert (Flint) (Silicon Dioxide (SiO2)) — sedimentary

Chert (Flint)

Silicon Dioxide (SiO2)

Quartz (Smoky/Clear variety) (Silicon Dioxide (SiO2)) — mineral

Quartz (Smoky/Clear variety)

Silicon Dioxide (SiO2)

Granite fragment (Phaneritic Igneous Rock (Granitic composition)) — igneous

Granite fragment

Phaneritic Igneous Rock (Granitic composition)

Dumortierite in Quartz (Silicon Dioxide with Aluminium Borosilicate (SiO2 + (Al,Fe7+)7(BO3)(SiO4)3O3)) — mineral

Dumortierite in Quartz

Silicon Dioxide with Aluminium Borosilicate (SiO2 + (Al,Fe7+)7(BO3)(SiO4)3O3)

Quartz (Milky/Iron-stained) (Silicon Dioxide (SiO2)) — mineral

Quartz (Milky/Iron-stained)

Silicon Dioxide (SiO2)

Quartz in Matrix (possibly with Biotite or Hornblende) (Quartz (Silicon Dioxide, SiO2) in Granitic Matrix) — igneous

Quartz in Matrix (possibly with Biotite or Hornblende)

Quartz (Silicon Dioxide, SiO2) in Granitic Matrix

Milky Quartz (Quartz (SiO2) with iron staining) — mineral

Milky Quartz

Quartz (SiO2) with iron staining

Chert (vuggy variety) (Microcrystalline silica (SiO2)) — sedimentary

Chert (vuggy variety)

Microcrystalline silica (SiO2)

Banded Jasper and Quartz Pebble (Silicified sedimentary rock / Chalcedony (SiO2)) — sedimentary

Banded Jasper and Quartz Pebble

Silicified sedimentary rock / Chalcedony (SiO2)

Yellow Calcite (Calcium Carbonate (CaCO3)) — mineral

Yellow Calcite

Calcium Carbonate (CaCO3)

Raw black tourmaline (likely schorl) (Schorl, sodium–iron tourmaline; approximately NaFe²⁺₃Al₆(BO₃)₃Si₆O₁₈(OH)₄) — mineral

Raw black tourmaline (likely schorl)

Schorl, sodium–iron tourmaline; approximately NaFe²⁺₃Al₆(BO₃)₃Si₆O₁₈(OH)₄

Gold (Native Gold (Au)) — mineral

Gold

Native Gold (Au)

Sandstone (with potential mineral staining/concretions) (Arenite (SiO2 based)) — sedimentary

Sandstone (with potential mineral staining/concretions)

Arenite (SiO2 based)

Quartz (Silicon Dioxide (SiO2)) — mineral

Quartz

Silicon Dioxide (SiO2)

Quartz (Silicon Dioxide (SiO2)) — mineral

Quartz

Silicon Dioxide (SiO2)

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

Quartz (Milky or Smoky)

Silicon Dioxide (SiO2)

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

Quartz (Milky Quartz)

Silicon Dioxide (SiO2)

Quartz (Milky/Clear variety) (Silicon Dioxide (SiO2)) — mineral

Quartz (Milky/Clear variety)

Silicon Dioxide (SiO2)

Chert (specifically Flint or Gray Chalcedony) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (specifically Flint or Gray Chalcedony)

Microcrystalline Quartz (SiO2)

Copper Bullion Round (Native Copper (refined), Cu) — mineral

Copper Bullion Round

Native Copper (refined), Cu

Clear Quartz (Silicon dioxide (SiO2)) — mineral

Clear Quartz

Silicon dioxide (SiO2)

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

Milky Quartz with Iron Inclusions

Silicon Dioxide (SiO2)

Jasper (Microcrystalline Quartz (SiO2)) — sedimentary

Jasper

Microcrystalline Quartz (SiO2)

Quartz / River Cobble (Silicon Dioxide (SiO2)) — mineral

Quartz / River Cobble

Silicon Dioxide (SiO2)

Yellow Chalcedony (common opal or chert variant) (Silicon Dioxide (SiO2)) — sedimentary (mineraloid/microcrystalline quartz)

Yellow Chalcedony (common opal or chert variant)

Silicon Dioxide (SiO2)

sedimentary (mineraloid/microcrystalline quartz)