Rock Identifier

Category

Organic (Geological Relative)

Browse organic (geological relative) specimens identified by the Rock Identifier community.

Selenite (Gypsum (CaSO4·2H2O), specifically the crystalline variety Selenite) — Mineral

Selenite

Gypsum (CaSO4·2H2O), specifically the crystalline variety Selenite

Rough Green Calcite (Calcite (Calcium Carbonate, CaCO3)) — mineral

Rough Green Calcite

Calcite (Calcium Carbonate, CaCO3)

Golden Sheen Obsidian (Obsidian (volcanic glass) with inclusions of gas bubbles and mineral crystals (e.g., hematite, magnetite) causing the sheen) — igneous

Golden Sheen Obsidian

Obsidian (volcanic glass) with inclusions of gas bubbles and mineral crystals (e.g., hematite, magnetite) causing the sheen

Bronzite (MgSiO3 (Enstatite with 10-30% FeSiO3 in solid solution)) — Mineral

Bronzite

MgSiO3 (Enstatite with 10-30% FeSiO3 in solid solution)

Amethyst (Quartz (SiO2) variety) — Mineral

Amethyst

Quartz (SiO2) variety

Clear Quartz (or Rock Crystal) (Quartz (SiO₂)) — Mineral

Clear Quartz (or Rock Crystal)

Quartz (SiO₂)

Amethyst (Quartz (SiO2) with trace iron impurities) — Mineral

Amethyst

Quartz (SiO2) with trace iron impurities

Quartzite (Quartzite (primarily SiO2)) — metamorphic

Quartzite

Quartzite (primarily SiO2)

Limestone (Sedimentary Rock (Primarily CaCO3)) — sedimentary

Limestone

Sedimentary Rock (Primarily CaCO3)

Banded Metamorphic Rock (likely Quartzite or Serpentinite/Soapstone) (Metamorphic Rock (possibly a banded Quartzite or a foliated Serpentinite/Talc Schist based on appearance, general term for such a rock is 'Banded Metamorphic Rock' or 'Gneiss' if pronounced banding of different minerals)) — Metamorphic

Banded Metamorphic Rock (likely Quartzite or Serpentinite/Soapstone)

Metamorphic Rock (possibly a banded Quartzite or a foliated Serpentinite/Talc Schist based on appearance, general term for such a rock is 'Banded Metamorphic Rock' or 'Gneiss' if pronounced banding of different minerals)

Quartz (beads) (SiO2 (Silicon Dioxide)) — Mineral

Quartz (beads)

SiO2 (Silicon Dioxide)

Granite (Granite (a felsic intrusive igneous rock)) — Igneous Rock

Granite

Granite (a felsic intrusive igneous rock)

Carnelian (Carnelian (a variety of Chalcedony, SiO2)) — Mineral

Carnelian

Carnelian (a variety of Chalcedony, SiO2)

Citrine Geode (or Druzy Citrine) (Silicon Dioxide (SiO₂) - a variety of Quartz) — Mineral

Citrine Geode (or Druzy Citrine)

Silicon Dioxide (SiO₂) - a variety of Quartz

Quartz (Quartz (SiO₂)) — Mineral

Quartz

Quartz (SiO₂)

Calcite (Calcite (Calcium Carbonate, CaCO3)) — mineral

Calcite

Calcite (Calcium Carbonate, CaCO3)

Gneiss (Gneiss (a metamorphic rock)) — Metamorphic

Gneiss

Gneiss (a metamorphic rock)

Calcite (likely a tumbled specimen) (Calcite (CaCO
3
)) — Mineral

Calcite (likely a tumbled specimen)

Calcite (CaCO 3 )

Banded Calcite (often sold as 'Mexican Onyx' or 'Green Onyx') (Calcite (CaCO3)) — sedimentary

Banded Calcite (often sold as 'Mexican Onyx' or 'Green Onyx')

Calcite (CaCO3)

Jade (likely Nephrite or Jadeite) (Nephrite (Ca2(Mg,Fe)5Si8O22(OH)2) or Jadeite (Na(Al,Fe3+)Si2O6)) — Mineral

Jade (likely Nephrite or Jadeite)

Nephrite (Ca2(Mg,Fe)5Si8O22(OH)2) or Jadeite (Na(Al,Fe3+)Si2O6)

Carnelian (Chalcedony (cryptocrystalline quartz), SiO2) — Mineral

Carnelian

Chalcedony (cryptocrystalline quartz), SiO2

Scoria (Scoria (a vesicular basalt or andesite)) — igneous

Scoria

Scoria (a vesicular basalt or andesite)

Amazonite (KAlSi3O8 (Potassium Feldspar, variety of Microcline)) — Mineral

Amazonite

KAlSi3O8 (Potassium Feldspar, variety of Microcline)

Blue Tiger's Eye (Riebeckite (crocidolite variety)) — Mineral

Blue Tiger's Eye

Riebeckite (crocidolite variety)

Chert (Chert (microcrystalline quartz)) — Sedimentary

Chert

Chert (microcrystalline quartz)

Blue Lace Agate (Chalcedony (a form of Quartz) - SiO2) — Mineral

Blue Lace Agate

Chalcedony (a form of Quartz) - SiO2

Greenschist (Greenschist facies metamorphic rock) — metamorphic

Greenschist

Greenschist facies metamorphic rock

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

Orthoclase Feldspar

KAlSi3O8 (Potassium Aluminum Silicate)

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

Amethyst (Quartz)

SiO2 (Silicon Dioxide)

Puddingstone (Jasper Conglomerate) (Conglomerate (specific type: Jasper Conglomerate or Hertfordshire Puddingstone)) — Sedimentary

Puddingstone (Jasper Conglomerate)

Conglomerate (specific type: Jasper Conglomerate or Hertfordshire Puddingstone)

River Rock / Stream Pebble (Fluvial Clast / Rounded Sedimentary Particle) — Sedimentary Rock (possibly composed of various minerals)

River Rock / Stream Pebble

Fluvial Clast / Rounded Sedimentary Particle

Sedimentary Rock (possibly composed of various minerals)

Blue Howlite (Dyed) (Calcium Borosilicate Hydroxide (Ca2B5SiO9(OH)5)) — mineral

Blue Howlite (Dyed)

Calcium Borosilicate Hydroxide (Ca2B5SiO9(OH)5)

Fossiliferous Limestone (Limestone (composed primarily of calcite with included fossils CaCO3)) — Sedimentary

Fossiliferous Limestone

Limestone (composed primarily of calcite with included fossils CaCO3)

Yellow Chalcedony (Chalcedony (a cryptocrystalline variety of Quartz, SiO₂)) — Mineral

Yellow Chalcedony

Chalcedony (a cryptocrystalline variety of Quartz, SiO₂)

Ironstone Concretion (likely) (Goethite/Hematite/Limonite cemented sediment) — Sedimentary Rock

Ironstone Concretion (likely)

Goethite/Hematite/Limonite cemented sediment

Sedimentary Rock

Unakite (Epidote-Feldspar rock (specifically, a variety of granite)) — Metamorphic rock

Unakite

Epidote-Feldspar rock (specifically, a variety of granite)

Metamorphic rock

Turquoise cabochon (Turquoise; hydrated copper–aluminum phosphate, approximately CuAl6(PO4)4(OH)8·4H2O (composition varies)) — gemstone

Turquoise cabochon

Turquoise; hydrated copper–aluminum phosphate, approximately CuAl6(PO4)4(OH)8·4H2O (composition varies)

Banded Jasper (Silicon Dioxide (SiO2)) — Mineral/Sedimentary Rock (as a cryptocrystalline variety of quartz)

Banded Jasper

Silicon Dioxide (SiO2)

Mineral/Sedimentary Rock (as a cryptocrystalline variety of quartz)

Moss Agate (Moss Agate (a variety of Chalcedony, SiO

₂)) — Mineral (specifically a variety of Chalcedony, which is microcrystalline Quartz)

Moss Agate

Moss Agate (a variety of Chalcedony, SiO ₂)

Mineral (specifically a variety of Chalcedony, which is microcrystalline Quartz)

Blue Apatite (Apatite, Ca5(PO4)3(F,Cl,OH)) — mineral

Blue Apatite

Apatite, Ca5(PO4)3(F,Cl,OH)

Limestone Pebble (Sedimentary Rock (Calcite, CaCO3)) — sedimentary

Limestone Pebble

Sedimentary Rock (Calcite, CaCO3)

Calcite (Calcite (CaCO₃)) — Mineral

Calcite

Calcite (CaCO₃)