Rock Identifier

Category

Man Made Object (Coin)

Browse man made object (coin) specimens identified by the Rock Identifier community.

Citrine (Silicon Dioxide (SiO2) with iron impurities) — mineral

Citrine

Silicon Dioxide (SiO2) with iron impurities

Unakite (Epidotized Granite) — metamorphic

Unakite

Epidotized Granite

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

Quartz (Milky/Gold-stained)

Silicon Dioxide (SiO2)

Milky Quartz (Silicon Dioxide (SiO2)) — mineral

Milky Quartz

Silicon Dioxide (SiO2)

Quartzite (Metamorphosed Quartz Sandstone (SiO2)) — metamorphic

Quartzite

Metamorphosed Quartz Sandstone (SiO2)

Apache Tear (Obsidian (Hydrated Silica / Amorphous Volcanic Glass)) — igneous

Apache Tear

Obsidian (Hydrated Silica / Amorphous Volcanic Glass)

Sandstone (Ferruginous) (Arenite (primarily SiO2 with Fe2O3/FeO(OH) cementing agents)) — sedimentary

Sandstone (Ferruginous)

Arenite (primarily SiO2 with Fe2O3/FeO(OH) cementing agents)

Agate (Bead Form) (Agate (Cryptocrystalline Quartz, SiO2)) — mineral

Agate (Bead Form)

Agate (Cryptocrystalline Quartz, SiO2)

Carnelian (Red Chalcedony) (Silicon Dioxide (SiO2)) — mineral

Carnelian (Red Chalcedony)

Silicon Dioxide (SiO2)

Tufa (Vesicular Limestone) (Tufa (form of Calcium Carbonate, CaCO3)) — sedimentary

Tufa (Vesicular Limestone)

Tufa (form of Calcium Carbonate, CaCO3)

Nephrite Jade (Nephrite (Ca2(Mg, Fe)5Si8O22(OH)2)) — metamorphic

Nephrite Jade

Nephrite (Ca2(Mg, Fe)5Si8O22(OH)2)

Emerald (Beryl (Be3Al2Si6O18 with Chromium/Vanadium impurities)) — mineral

Emerald

Beryl (Be3Al2Si6O18 with Chromium/Vanadium impurities)

Orthoclase Feldspar (KAlSi3O8 (Potassium Aluminum Silicate)) — Mineral

Orthoclase Feldspar

KAlSi3O8 (Potassium Aluminum Silicate)

Banded Gneiss (River Rock/Pebble) (Gneiss (specifically a banded variety often found as a river rock)) — Metamorphic Rock

Banded Gneiss (River Rock/Pebble)

Gneiss (specifically a banded variety often found as a river rock)

Metamorphic Rock

White Quartz Pebble (Silicon Dioxide (SiO2)) — mineral

White Quartz Pebble

Silicon Dioxide (SiO2)

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

Milky Quartz

Quartz (Silicon Dioxide - SiO2)

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

Milky Quartz Pebble

Silicon Dioxide (SiO2)

Quartzite (River Stone) (Quartzite (SiO2)) — metamorphic

Quartzite (River Stone)

Quartzite (SiO2)

Milky Quartz (Silicon Dioxide (SiO2)) — mineral

Milky Quartz

Silicon Dioxide (SiO2)

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

Green Chert (Jasper)

Silicon Dioxide (SiO2)

Basalt (River Rock Cobble) (Extrusive mafic volcanic rock (Basalt)) — igneous

Basalt (River Rock Cobble)

Extrusive mafic volcanic rock (Basalt)

Basalt (River Pebble) (Extrusive mafic igneous rock) — igneous

Basalt (River Pebble)

Extrusive mafic igneous rock

Quartzite (Quartzite (Primary mineral: SiO2)) — metamorphic

Quartzite

Quartzite (Primary mineral: SiO2)

Chert (Yellow Jasper variant) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (Yellow Jasper variant)

Microcrystalline Quartz (SiO2)

Quartz Pebble (Chalcedony/Agate) (Silicon Dioxide (SiO2)) — Mineral

Quartz Pebble (Chalcedony/Agate)

Silicon Dioxide (SiO2)

Banded Iron Formation (BIF) / Tiger Iron variety (Banded Iron Formation (composed primarily of Magnetite Fe3O4, Hematite Fe2O3, and Chert/Quartz SiO2)) — sedimentary

Banded Iron Formation (BIF) / Tiger Iron variety

Banded Iron Formation (composed primarily of Magnetite Fe3O4, Hematite Fe2O3, and Chert/Quartz SiO2)

Amethyst (Geode) (Silicon Dioxide (SiO2) with iron impurities) — mineral

Amethyst (Geode)

Silicon Dioxide (SiO2) with iron impurities

Amethyst (Silicon Dioxide (SiO2) with iron impurities) — Mineral

Amethyst

Silicon Dioxide (SiO2) with iron impurities

Citrine Quartz (Silicon Dioxide (SiO2) with iron impurities) — mineral

Citrine Quartz

Silicon Dioxide (SiO2) with iron impurities

Clear Quartz (Silicon dioxide (SiO2)) — mineral

Clear Quartz

Silicon dioxide (SiO2)

Chert (specifically Red Chert or Jasper) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (specifically Red Chert or Jasper)

Microcrystalline Quartz (SiO2)

Gneiss (Gneiss (High-grade metamorphic rock)) — metamorphic

Gneiss

Gneiss (High-grade metamorphic rock)

Milky Quartz (Silicon Dioxide (SiO2)) — mineral

Milky Quartz

Silicon Dioxide (SiO2)

Milky Quartz (Silicon Dioxide (SiO2)) — mineral

Milky Quartz

Silicon Dioxide (SiO2)

Granitic Pegmatite (Coarse-grained Igneous Rock (Granitic composition: KAlSi3O8, SiO2)) — igneous

Granitic Pegmatite

Coarse-grained Igneous Rock (Granitic composition: KAlSi3O8, SiO2)

Chert (Jasper/Flint variety) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (Jasper/Flint variety)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Sandstone (with Iron Staining) (Arenite (composed primarily of SiO2 with Fe2O3 staining)) — sedimentary

Sandstone (with Iron Staining)

Arenite (composed primarily of SiO2 with Fe2O3 staining)

Basalt River Pebble (Basalt (Aphanitic Mafic Igneous Rock)) — igneous

Basalt River Pebble

Basalt (Aphanitic Mafic Igneous Rock)

Red Sandstone (Arenite (Ferruginous Sandstone)) — sedimentary

Red Sandstone

Arenite (Ferruginous Sandstone)

Gastropod Fossil (Snail Internal Mold) (Gastropoda; internal mold (steinkern), often composed of Calcium Carbonate (CaCO3) or Silica (SiO2)) — sedimentary

Gastropod Fossil (Snail Internal Mold)

Gastropoda; internal mold (steinkern), often composed of Calcium Carbonate (CaCO3) or Silica (SiO2)

Gastropod Internal Mold (Steinkern) (Class Gastropoda fossil mold (Phylum Mollusca)) — sedimentary

Gastropod Internal Mold (Steinkern)

Class Gastropoda fossil mold (Phylum Mollusca)

Quartzite (River Cobble) (Metamorphosed Quartz Sandstone (SiO2)) — metamorphic

Quartzite (River Cobble)

Metamorphosed Quartz Sandstone (SiO2)