Rock Identifier

Category

Organic Gemstone (Not A Rock)

Browse organic gemstone (not a rock) specimens identified by the Rock Identifier community.

Quartzite (Quartzite (SiO2)) — metamorphic

Quartzite

Quartzite (SiO2)

Dendritic Moss Agate (Chalcedony (Silicon Dioxide, SiO2) with inclusions) — mineral

Dendritic Moss Agate

Chalcedony (Silicon Dioxide, SiO2) with inclusions

Blue Calcite (Calcium Carbonate (CaCO3)) — mineral

Blue Calcite

Calcium Carbonate (CaCO3)

Chalk / Sedimentary Limestone (Calcium Carbonate (CaCO3) - Biogenic Sedimentary Rock) — sedimentary

Chalk / Sedimentary Limestone

Calcium Carbonate (CaCO3) - Biogenic Sedimentary Rock

Moss Agate (Chalcedony (Silicon Dioxide) with dendritic inclusions (SiO2)) — Mineral

Moss Agate

Chalcedony (Silicon Dioxide) with dendritic inclusions (SiO2)

Moss Agate (Silicon Dioxide with inclusions (SiO2)) — mineral

Moss Agate

Silicon Dioxide with inclusions (SiO2)

Moss Agate (Silicon Dioxide (SiO2) with mineral inclusions) — Mineral

Moss Agate

Silicon Dioxide (SiO2) with mineral inclusions

Green Moss Agate (Agate (Silicon Dioxide, SiO2) with inclusions of hornblende or chlorite) — mineral

Green Moss Agate

Agate (Silicon Dioxide, SiO2) with inclusions of hornblende or chlorite

Moss Agate (Silicon Dioxide (SiO2) with inclusions of manganese or iron oxide) — mineral

Moss Agate

Silicon Dioxide (SiO2) with inclusions of manganese or iron oxide

Diopside (likely Chromian Diopside) (Diopside, part of Clinopyroxene family of inosilicates. Chemical formula: CaMgSi2O6. The green variety is often Chromian Diopside due to chromium impurities.) — mineral

Diopside (likely Chromian Diopside)

Diopside, part of Clinopyroxene family of inosilicates. Chemical formula: CaMgSi2O6. The green variety is often Chromian Diopside due to chromium impurities.

Green Moss Agate (Silicon Dioxide with inclusions (SiO2 + Mn/Fe)) — sedimentary

Green Moss Agate

Silicon Dioxide with inclusions (SiO2 + Mn/Fe)

Red Moss Agate (Jasper) (Silicon Dioxide (SiO2) with Iron Oxide inclusions) — sedimentary

Red Moss Agate (Jasper)

Silicon Dioxide (SiO2) with Iron Oxide inclusions

Moss Agate (Chalcedony (Silicon Dioxide, SiO2) with dendritic inclusions) — mineral

Moss Agate

Chalcedony (Silicon Dioxide, SiO2) with dendritic inclusions

Moss Agate (Chalcedony (SiO2) with inclusions of manganese or iron oxide) — mineral

Moss Agate

Chalcedony (SiO2) with inclusions of manganese or iron oxide

Chert (Iron-stained) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (Iron-stained)

Microcrystalline Quartz (SiO2)

Greenstone (possibly Basalt or Greenschist) (Greenschist (composed primarily of chlorite, actinolite, and epidote)) — Metamorphic (low-grade)

Greenstone (possibly Basalt or Greenschist)

Greenschist (composed primarily of chlorite, actinolite, and epidote)

Metamorphic (low-grade)

Green Moss Agate (Agate (Silicon Dioxide - SiO2 with inclusions of Manganese/Iron oxides)) — mineral

Green Moss Agate

Agate (Silicon Dioxide - SiO2 with inclusions of Manganese/Iron oxides)

Moss Agate (Chalcedony (SiO2) with inclusions of manganese or iron oxides) — mineral

Moss Agate

Chalcedony (SiO2) with inclusions of manganese or iron oxides

Moss Agate (Silicon Dioxide with inclusions (SiO2 + Mn/Fe/Chlorite)) — mineral

Moss Agate

Silicon Dioxide with inclusions (SiO2 + Mn/Fe/Chlorite)

Chert (and Quartz Gravel) (Chert (Cryptocrystalline Quartz, SiO2)) — sedimentary

Chert (and Quartz Gravel)

Chert (Cryptocrystalline Quartz, SiO2)

Dinosaur Fossil (Skull) (Dinosauria fossilis (Petrified Hydroxyapatite / Calcium Carbonate)) — sedimentary

Dinosaur Fossil (Skull)

Dinosauria fossilis (Petrified Hydroxyapatite / Calcium Carbonate)

Chert (specifically Gray/Tan Bedded Chert) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (specifically Gray/Tan Bedded Chert)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Moss Agate (Silicon Dioxide (SiO2) with inclusions of hornblende or chlorite) — mineral

Moss Agate

Silicon Dioxide (SiO2) with inclusions of hornblende or chlorite

Dendritic Limestone (Calcite with Manganese Oxide (Manganese Dendrites)) — sedimentary

Dendritic Limestone

Calcite with Manganese Oxide (Manganese Dendrites)

Almandine Garnet in Matrix (Almandine, Fe3Al2(SiO4)3) — metamorphic

Almandine Garnet in Matrix

Almandine, Fe3Al2(SiO4)3

Green Moss Agate (Silicon Dioxide with inclusions (SiO2)) — sedimentary

Green Moss Agate

Silicon Dioxide with inclusions (SiO2)

Green Aventurine (Silicon dioxide with Fuscite inclusions (SiO2 + K(Al,Cr)2AlSi3O10(OH)2)) — mineral

Green Aventurine

Silicon dioxide with Fuscite inclusions (SiO2 + K(Al,Cr)2AlSi3O10(OH)2)

Green Moss Agate (Agate (Silicon Dioxide - SiO2) with inclusions of hornblende or chlorite) — mineral

Green Moss Agate

Agate (Silicon Dioxide - SiO2) with inclusions of hornblende or chlorite

Dendritic Agate / Moss Agate (Silicon Dioxide (SiO2) with Manganese/Iron oxide inclusions) — mineral

Dendritic Agate / Moss Agate

Silicon Dioxide (SiO2) with Manganese/Iron oxide inclusions

Chert (often called Flint when dark) (Sedimentary cryptocrystalline quartz (SiO2)) — sedimentary

Chert (often called Flint when dark)

Sedimentary cryptocrystalline quartz (SiO2)

Granite (tumbled pebble) (Granite (Plutonic Igneous Rock)) — Igneous Rock

Granite (tumbled pebble)

Granite (Plutonic Igneous Rock)

Moss Agate (Silicon Dioxide (SiO2) with inclusions of manganese or iron oxides) — mineral

Moss Agate

Silicon Dioxide (SiO2) with inclusions of manganese or iron oxides

Moss Agate (Silicon Dioxide (SiO2) with mineral inclusions of hornblende or chlorite) — Mineral (variety of Chalcedony)

Moss Agate

Silicon Dioxide (SiO2) with mineral inclusions of hornblende or chlorite

Mineral (variety of Chalcedony)

Limestone (Calcareous sedimentary rock (primarily CaCO3)) — sedimentary

Limestone

Calcareous sedimentary rock (primarily CaCO3)

Pink Opal (Hydrated silicon dioxide (SiO2·nH2O) with inclusions) — mineral

Pink Opal

Hydrated silicon dioxide (SiO2·nH2O) with inclusions

Anyolite (Ruby in Zoisite) (Zoisite with inclusions of Corundum; Ca2Al3(SiO4)3(OH) + Al2O3) — metamorphic

Anyolite (Ruby in Zoisite)

Zoisite with inclusions of Corundum; Ca2Al3(SiO4)3(OH) + Al2O3

Moss Agate (Silicon Dioxide with inclusions (SiO2 + impurities)) — mineral

Moss Agate

Silicon Dioxide with inclusions (SiO2 + impurities)

Moss Agate (Silicon Dioxide (SiO2) with inclusions of Manganese or Iron oxide) — mineral

Moss Agate

Silicon Dioxide (SiO2) with inclusions of Manganese or Iron oxide

Chert (Siliceous sedimentary rock (predominantly microcrystalline quartz, SiO2)) — Sedimentary

Chert

Siliceous sedimentary rock (predominantly microcrystalline quartz, SiO2)

Calcite (Calcite (CaCO₃)) — Mineral

Calcite

Calcite (CaCO₃)

Tanzanite (Rough) (Blue Zoisite (Ca2Al3(SiO4)3(OH))) — mineral

Tanzanite (Rough)

Blue Zoisite (Ca2Al3(SiO4)3(OH))

Fossilized Coral (Petoskey-like or Favosites) (Anthozoa (Fossilized Coral)) — sedimentary

Fossilized Coral (Petoskey-like or Favosites)

Anthozoa (Fossilized Coral)