Rock Identifier

Category

Man Made Object (Coin)

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

Diorite (Spotted or Dalmatian Stone pattern) (Diorite) — igneous

Diorite (Spotted or Dalmatian Stone pattern)

Diorite

igneous
Chert (Common Opal/Agate inclusion) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (Common Opal/Agate inclusion)

Microcrystalline Quartz (SiO2)

sedimentary
Granite (Granite) — igneous

Granite

Granite

igneous
The user-provided image does not contain a rock or mineral specimen — N/A

The user-provided image does not contain a rock or mineral specimen

N/A
Anthracite Coal (Anthracite (Carbon-based metamorphic rock)) — metamorphic

Anthracite Coal

Anthracite (Carbon-based metamorphic rock)

metamorphic
Serpentine (Serpentine-group ((Mg,Fe,Ni,Al,Zn,Mn)3(Si,Al,Fe)2O5(OH)4)) — metamorphic

Serpentine

Serpentine-group ((Mg,Fe,Ni,Al,Zn,Mn)3(Si,Al,Fe)2O5(OH)4)

metamorphic
Chert (Gravel Bit) (Microcrystalline silica (SiO2)) — sedimentary

Chert (Gravel Bit)

Microcrystalline silica (SiO2)

sedimentary
Basalt (Basalt (Mafic Extrusive Igneous Rock)) — igneous

Basalt

Basalt (Mafic Extrusive Igneous Rock)

igneous
Sandstone (likely Greywacke variant) (Arenite) — sedimentary

Sandstone (likely Greywacke variant)

Arenite

sedimentary
Feldspathic Granite (likely Syenite or Granite Pegmatite) (Phaneritic Acidic Igneous Rock (KAlSi3O8 dominant with SiO2)) — igneous

Feldspathic Granite (likely Syenite or Granite Pegmatite)

Phaneritic Acidic Igneous Rock (KAlSi3O8 dominant with SiO2)

igneous
Garnet-Bearing Gneiss (Almandine-Garnet Gneiss) — metamorphic

Garnet-Bearing Gneiss

Almandine-Garnet Gneiss

metamorphic
Granite (Granite (a plutonic igneous rock)) — Igneous

Granite

Granite (a plutonic igneous rock)

Igneous
Wood Beads (Palmwood/Ebony) (Various species for wood, but often refers to woods like Palmwood (e.g., Borassus flabellifer) or Ebony (Diospyros spp.) for their distinctive grain and hardness.) — Organic Gem Material (Botanical)

Wood Beads (Palmwood/Ebony)

Various species for wood, but often refers to woods like Palmwood (e.g., Borassus flabellifer) or Ebony (Diospyros spp.) for their distinctive grain and hardness.

Organic Gem Material (Botanical)
Ocean Jasper (Sea Jasper) (Spherulitic Chalcedony (SiO2)) — sedimentary

Ocean Jasper (Sea Jasper)

Spherulitic Chalcedony (SiO2)

sedimentary
Banded Agate (Brazilian Agate Slice) (Chalcedony (Silicon Dioxide / SiO2)) — Mineral

Banded Agate (Brazilian Agate Slice)

Chalcedony (Silicon Dioxide / SiO2)

Mineral
Mahogany Obsidian (Obsidian (SiO2 + Fe2O3)) — igneous

Mahogany Obsidian

Obsidian (SiO2 + Fe2O3)

igneous
Granite (Granite (Main minerals: Quartz SiO2, Feldspar KAlSi3O8, Mica)) — igneous

Granite

Granite (Main minerals: Quartz SiO2, Feldspar KAlSi3O8, Mica)

igneous
Hematite with Magnetite (Iron Oxide (Fe2O3)) — mineral

Hematite with Magnetite

Iron Oxide (Fe2O3)

mineral
Granite (Granite) — igneous

Granite

Granite

igneous
Diamond (Diamond (C)) — Mineral

Diamond

Diamond (C)

Mineral
Basalt (Basalt (comprising plagioclase, pyroxene, and olivine)) — igneous

Basalt

Basalt (comprising plagioclase, pyroxene, and olivine)

igneous
General Gravel (River Rock/River Stones) (Mixed Lithic Sediments (Conglomerate Clasts)) — sedimentary

General Gravel (River Rock/River Stones)

Mixed Lithic Sediments (Conglomerate Clasts)

sedimentary
Diorite Gneiss (Foliated Diorite Gneiss) — metamorphic

Diorite Gneiss

Foliated Diorite Gneiss

metamorphic
Basalt (Basalt (Mafic volcanic rock)) — igneous

Basalt

Basalt (Mafic volcanic rock)

igneous
Black Onyx (Cryptocrystalline Quartz (SiO2)) — mineral

Black Onyx

Cryptocrystalline Quartz (SiO2)

mineral
Amber (and Citrine Quartz) (Succinite (Amber) and Silicon Dioxide (SiO2)) — Organic Mineraloid and Mineral

Amber (and Citrine Quartz)

Succinite (Amber) and Silicon Dioxide (SiO2)

Organic Mineraloid and Mineral
Breciated Limestone with Calcite Veins (Sedimentary Breccia (CaCO3)) — sedimentary

Breciated Limestone with Calcite Veins

Sedimentary Breccia (CaCO3)

sedimentary
Red Coral (Precious Coral) (Corallium rubrum (Calcium Carbonate, CaCO3)) — sedimentary

Red Coral (Precious Coral)

Corallium rubrum (Calcium Carbonate, CaCO3)

sedimentary
Basalt with Granite Inclusions (Xenoliths) (Mafic igneous rock (Basalt) with Sialic minerals) — igneous

Basalt with Granite Inclusions (Xenoliths)

Mafic igneous rock (Basalt) with Sialic minerals

igneous
Stromatolite (Biogenic Sedimentary Rock (composed predominantly of CaCO3)) — sedimentary

Stromatolite

Biogenic Sedimentary Rock (composed predominantly of CaCO3)

sedimentary
Quartz Geode (partially formed/chalcedony with iron staining) (Quartz (SiO2) with Chalcedony (cryptocrystalline quartz) and likely Iron Oxides/Hydroxides) — Mineral/Sedimentary Rock Feature

Quartz Geode (partially formed/chalcedony with iron staining)

Quartz (SiO2) with Chalcedony (cryptocrystalline quartz) and likely Iron Oxides/Hydroxides

Mineral/Sedimentary Rock Feature
Snowflake Obsidian (Spherulitic Volcanic Glass (SiO2 + impurities)) — igneous

Snowflake Obsidian

Spherulitic Volcanic Glass (SiO2 + impurities)

igneous
Druzy Quartz Geode (likely Smokey Quartz variety) (Silicon Dioxide (SiO2) - specifically a geode formation lined with druzy quartz crystals, with a likely brownish hue indicating smokey quartz.) — Mineral structure/Rock

Druzy Quartz Geode (likely Smokey Quartz variety)

Silicon Dioxide (SiO2) - specifically a geode formation lined with druzy quartz crystals, with a likely brownish hue indicating smokey quartz.

Mineral structure/Rock
Carnelian (a variety of Chalcedony) (Silicon Dioxide (SiO2) with iron oxide impurities) — mineral

Carnelian (a variety of Chalcedony)

Silicon Dioxide (SiO2) with iron oxide impurities

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

Honey Calcite

Calcium Carbonate (CaCO3)

mineral
Ocean Jasper (Spherulitic Chalcedony (SiO2)) — mineral

Ocean Jasper

Spherulitic Chalcedony (SiO2)

mineral
Chert Pebble (Jasperoid/Flint) (Silicon Dioxide (SiO2) - cryptocrystalline quartz) — Sedimentary

Chert Pebble (Jasperoid/Flint)

Silicon Dioxide (SiO2) - cryptocrystalline quartz

Sedimentary
Gneiss (Schistose) (Gneiss) — metamorphic

Gneiss (Schistose)

Gneiss

metamorphic
Granite (Phaneritic Felsic Igneous Rock (Granite)) — igneous

Granite

Phaneritic Felsic Igneous Rock (Granite)

igneous
Gneiss (Gneissic Metamorphic Rock) — metamorphic

Gneiss

Gneissic Metamorphic Rock

metamorphic
Basalt (Basalt (Mafic volcanic rock)) — igneous

Basalt

Basalt (Mafic volcanic rock)

igneous
Brecciated Jasper (Silicon Dioxide (SiO2) with Hematite inclusions) — sedimentary

Brecciated Jasper

Silicon Dioxide (SiO2) with Hematite inclusions

sedimentary