Rock Identifier

Category

Man Made Object (Coin)

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

Quartzite (Quartzite (mostly SiO2)) — metamorphic

Quartzite

Quartzite (mostly SiO2)

Hag Stone (Perforated Sedimentary Rock (typically Limestone or Sandstone)) — sedimentary

Hag Stone

Perforated Sedimentary Rock (typically Limestone or Sandstone)

Chert (specifically Flint) (Microcrystalline quartz (SiO2)) — sedimentary

Chert (specifically Flint)

Microcrystalline quartz (SiO2)

Satin Spar (Selenite) (Gypsum (Calcium Sulfate Dihydrate) - CaSO4·2H2O) — mineral

Satin Spar (Selenite)

Gypsum (Calcium Sulfate Dihydrate) - CaSO4·2H2O

Clear Quartz (Silicon Dioxide (SiO2)) — mineral

Clear Quartz

Silicon Dioxide (SiO2)

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

Citrine

Silicon Dioxide (SiO2) with iron impurities

Diorite (Diorite (Intermediate intrusive igneous rock)) — igneous

Diorite

Diorite (Intermediate intrusive igneous rock)

Banded Chert (Agate-like Flint) (Silicon Dioxide (SiO2) - Microcrystalline Quartz) — sedimentary

Banded Chert (Agate-like Flint)

Silicon Dioxide (SiO2) - Microcrystalline Quartz

Quartz Pebble (Silicon Dioxide (SiO2)) — mineral

Quartz Pebble

Silicon Dioxide (SiO2)

Chert (specifically Flint) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (specifically Flint)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Quartz (likely macrocrystalline variety) (Quartz (SiO₂)) — Mineral

Quartz (likely macrocrystalline variety)

Quartz (SiO₂)

Chert (Limestone-based) (Silicon dioxide (SiO2)) — sedimentary

Chert (Limestone-based)

Silicon dioxide (SiO2)

Fossilized Coral (Scleractinia (fossil order), primarily Calcium Carbonate (CaCO3)) — sedimentary

Fossilized Coral

Scleractinia (fossil order), primarily Calcium Carbonate (CaCO3)

Chert (Chalcedony/Agate) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (Chalcedony/Agate)

Microcrystalline Quartz (SiO2)

Goniatite Fossil (Goniatitida (Order), fossilized in limestone/calcite (CaCO3)) — sedimentary

Goniatite Fossil

Goniatitida (Order), fossilized in limestone/calcite (CaCO3)

Ammonite Fossil (Ammonoidea (typically preserved as Calcite CaCO3 or Pyrite FeS2)) — sedimentary

Ammonite Fossil

Ammonoidea (typically preserved as Calcite CaCO3 or Pyrite FeS2)

Ammonite Fossil (Ammonoidea (primarily composed of Calcite, CaCO3, or Pyrite)) — sedimentary

Ammonite Fossil

Ammonoidea (primarily composed of Calcite, CaCO3, or Pyrite)

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

Milky Quartz Geode Fragment

Silicon Dioxide (SiO2)

Sandstone (Arenite (primarily SiO2)) — sedimentary

Sandstone

Arenite (primarily SiO2)

Limestone (Calcium Carbonate (CaCO3)) — sedimentary

Limestone

Calcium Carbonate (CaCO3)

Quartz (Rock Crystal) (Quartz (SiO₂ - Silicon Dioxide)) — Mineral

Quartz (Rock Crystal)

Quartz (SiO₂ - Silicon Dioxide)

Moqui Marble (Moqui Ball) (Ironstone Concretion (Goethite/Hematite cemented Sandstone)) — sedimentary

Moqui Marble (Moqui Ball)

Ironstone Concretion (Goethite/Hematite cemented Sandstone)

Yellow Quartzite (Quartzite (SiO2)) — metamorphic

Yellow Quartzite

Quartzite (SiO2)

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

Quartz

Quartz (SiO₂ - Silicon Dioxide)

Granite (Granite (Mainly Quartz: SiO2, Feldspar: KAlSi3O8 – NaAlSi3O8 – CaAl2Si2O8, and Mica)) — igneous

Granite

Granite (Mainly Quartz: SiO2, Feldspar: KAlSi3O8 – NaAlSi3O8 – CaAl2Si2O8, and Mica)

Gold Nugget (Native Gold (Au)) — mineral

Gold Nugget

Native Gold (Au)

Hag Stone (Calcareous sedimentary rock (often Chert, Flint, or Limestone)) — sedimentary

Hag Stone

Calcareous sedimentary rock (often Chert, Flint, or Limestone)

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

Chert (Nodule)

Silicon Dioxide (SiO2)

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

Sandstone

Arenite (composed primarily of Quartz, SiO2)

Greenstone (Greenschist) (Greenschist (composed of Chlorite, Epidote, and Actinolite)) — metamorphic

Greenstone (Greenschist)

Greenschist (composed of Chlorite, Epidote, and Actinolite)

Chert (Flint Nodules) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (Flint Nodules)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Limonite (with goethite) (Hydrated Iron(III) Oxide-Hydroxide (FeO(OH)·nH2O)) — mineral

Limonite (with goethite)

Hydrated Iron(III) Oxide-Hydroxide (FeO(OH)·nH2O)

Orange Calcite (Calcite (CaCO3)) — Mineral

Orange Calcite

Calcite (CaCO3)

Smoky Quartz (Silicon Dioxide (SiO2)) — mineral

Smoky Quartz

Silicon Dioxide (SiO2)

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

Amethyst (Druze)

Silicon Dioxide (SiO2) with iron impurities

Granodiorite (Phaneritic intrusive igneous rock (Granodiorite)) — igneous

Granodiorite

Phaneritic intrusive igneous rock (Granodiorite)

Sandstone (Quartzite Pebble) (Arenite / Metamorphosed Sandstone (SiO2)) — sedimentary

Sandstone (Quartzite Pebble)

Arenite / Metamorphosed Sandstone (SiO2)

Chert (Chert Nodule) (Microcrystalline quartz (SiO2)) — sedimentary

Chert (Chert Nodule)

Microcrystalline quartz (SiO2)

Granite (Granite (a common rock type, not a single mineral species)) — Igneous

Granite

Granite (a common rock type, not a single mineral species)

Quartz (Quartz (SiO₂)) — Mineral

Quartz

Quartz (SiO₂)

Chert (Arrowhead or Projectile Point) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (Arrowhead or Projectile Point)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Red Jasper (Silicon dioxide (SiO2) with iron oxide impurities) — mineral

Red Jasper

Silicon dioxide (SiO2) with iron oxide impurities