Rock Identifier

Category

Organic (Non Geological)

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

Travertine (Calcareous Tufa (CaCO3)) — sedimentary

Travertine

Calcareous Tufa (CaCO3)

Obsidian (Volcanic Glass (predominantly SiO2 – Silicon Dioxide, but non-crystalline)) — Igneous

Obsidian

Volcanic Glass (predominantly SiO2 – Silicon Dioxide, but non-crystalline)

Septarian Nodule (Septarian Concretion (CaCO3 with Siderite/Calcite/Aragonite)) — sedimentary

Septarian Nodule

Septarian Concretion (CaCO3 with Siderite/Calcite/Aragonite)

Petrified Wood (Silicified Wood (primarily SiO2 - Silicon Dioxide / Chalcedony)) — metamorphic

Petrified Wood

Silicified Wood (primarily SiO2 - Silicon Dioxide / Chalcedony)

Septarian Nodule (Dragon Stone) (Septarian Nodule (Calcium Carbonate/Aragonite/Calcite Concretion)) — sedimentary

Septarian Nodule (Dragon Stone)

Septarian Nodule (Calcium Carbonate/Aragonite/Calcite Concretion)

Fancy Jasper (Agate/Chert mix) (Silicon Dioxide (SiO2) with impurities) — sedimentary

Fancy Jasper (Agate/Chert mix)

Silicon Dioxide (SiO2) with impurities

Ironstone Concretion (Siderite or Hematite Concretion) — sedimentary

Ironstone Concretion

Siderite or Hematite Concretion

Red Siltstone (or Red Shale) (Clastic Sedimentary Rock (Composition: primarily Quartz, Clay minerals, and Hematite Fe2O3)) — sedimentary

Red Siltstone (or Red Shale)

Clastic Sedimentary Rock (Composition: primarily Quartz, Clay minerals, and Hematite Fe2O3)

Water and Silt (Sedimentary Environment) (Suspended Sediment / H2O (dihydrogen monoxide)) — sedimentary

Water and Silt (Sedimentary Environment)

Suspended Sediment / H2O (dihydrogen monoxide)

Limestone (Calcium Carbonate (CaCO3)) — sedimentary

Limestone

Calcium Carbonate (CaCO3)

Baroque Pearl (Calcium Carbonate (Aragonite or Calcite) and Conchiolin) — Organic Gemstone

Baroque Pearl

Calcium Carbonate (Aragonite or Calcite) and Conchiolin

Organic Gemstone

Pink Opal / Peruvian Opal (Hydrated amorphous silicon dioxide (SiO2·nH2O)) — Mineral

Pink Opal / Peruvian Opal

Hydrated amorphous silicon dioxide (SiO2·nH2O)

Apache Tear (Obsidian (Hydrated Volcanic Glass - SiO2)) — igneous

Apache Tear

Obsidian (Hydrated Volcanic Glass - SiO2)

Banded Chert (Microcrystalline silicon dioxide (SiO2)) — sedimentary

Banded Chert

Microcrystalline silicon dioxide (SiO2)

Travertine (often colloquially called Tufa) (Chemical Sedimentary Calcium Carbonate (CaCO3)) — sedimentary

Travertine (often colloquially called Tufa)

Chemical Sedimentary Calcium Carbonate (CaCO3)

Peridot (Olivine ((Mg,Fe)2SiO4)) — Mineral

Peridot

Olivine ((Mg,Fe)2SiO4)

Obsidian (specifically Silver Sheen Obsidian) (Volcanic Glass (approx. 70–75% SiO2 plus MgO, Fe3O4)) — igneous

Obsidian (specifically Silver Sheen Obsidian)

Volcanic Glass (approx. 70–75% SiO2 plus MgO, Fe3O4)

Moss Agate (Silicon Dioxide (SiO2) with inclusions of manganese or iron oxides) — Mineral (Variety of Chalcedony)

Moss Agate

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

Mineral (Variety of Chalcedony)

Black Marble with Quartz Veining (Metamorphosed Limestone (Recrystallized CaCO3)) — metamorphic

Black Marble with Quartz Veining

Metamorphosed Limestone (Recrystallized CaCO3)

Fossilized Gastropod (Snail) (Class Gastropoda (internal mold or 'steinkern')) — sedimentary

Fossilized Gastropod (Snail)

Class Gastropoda (internal mold or 'steinkern')

Quartz (likely) or a Quartzite Pebble (Silicon dioxide (SiO2) for quartz. If it's quartzite, it's a metamorphic rock primarily composed of quartz.) — Mineral, specifically a detrital grain

Quartz (likely) or a Quartzite Pebble

Silicon dioxide (SiO2) for quartz. If it's quartzite, it's a metamorphic rock primarily composed of quartz.

Mineral, specifically a detrital grain

Sandstone (with carbonaceous plant fragments) (Arenite (composed primarily of SiO2)) — sedimentary

Sandstone (with carbonaceous plant fragments)

Arenite (composed primarily of SiO2)

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

Green Moss Agate

Silicon Dioxide (SiO2) with inclusions of hornblende or chlorite

Anthracite Coal (Anthracite (a variety of coal, predominantly carbon)) — Sedimentary Rock (Metamorphosed)

Anthracite Coal

Anthracite (a variety of coal, predominantly carbon)

Sedimentary Rock (Metamorphosed)

Basaltic Tuff / Volcanic Breccia (Pyroclastic Breccia / Lithic Tuff) — igneous

Basaltic Tuff / Volcanic Breccia

Pyroclastic Breccia / Lithic Tuff

Pyrite (Iron Pyrite (FeS2)) — mineral

Pyrite

Iron Pyrite (FeS2)

Petrified Wood (Silicified Wood (SiO2)) — sedimentary

Petrified Wood

Silicified Wood (SiO2)

Quartz Geode (Silicon Dioxide (SiO2) within a secondary sedimentary structure) — sedimentary

Quartz Geode

Silicon Dioxide (SiO2) within a secondary sedimentary structure

Petrified Wood (Silicified Wood (SiO2)) — sedimentary

Petrified Wood

Silicified Wood (SiO2)

Red Coral (Corallium rubrum (for precious red coral), although other species like Corallium japonicum and Paracorallium are also used.) — Organic Gemstone (not a rock or mineral in the traditional sense, but bio-mineralized material)

Red Coral

Corallium rubrum (for precious red coral), although other species like Corallium japonicum and Paracorallium are also used.

Organic Gemstone (not a rock or mineral in the traditional sense, but bio-mineralized material)

Quartz Geode (Silicon Dioxide (SiO2)) — sedimentary

Quartz Geode

Silicon Dioxide (SiO2)

Shungite (Carbonaceous rock (primarily amorphous carbon)) — Mineraloid

Shungite

Carbonaceous rock (primarily amorphous carbon)

Man-made Metal Pin (Non-geological) (Antimony-Lead Alloy or Zinc/Brass Base with Electroplating) — Metal Alloy / Manufactured Artifact

Man-made Metal Pin (Non-geological)

Antimony-Lead Alloy or Zinc/Brass Base with Electroplating

Metal Alloy / Manufactured Artifact

Feldspar-rich Quartzite (Feldspathic Quartzite (Metamorphosed Sandstone)) — Metamorphic

Feldspar-rich Quartzite

Feldspathic Quartzite (Metamorphosed Sandstone)

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

Ironstone Concretion (Limonite/Hematite Nodules) (Ironstone (principally Limonite FeO(OH)·nH2O or Hematite Fe2O3 mixed with silica/clay)) — sedimentary

Ironstone Concretion (Limonite/Hematite Nodules)

Ironstone (principally Limonite FeO(OH)·nH2O or Hematite Fe2O3 mixed with silica/clay)

Zebra Marble (Metamorphosed Alabaster/Limestone (CaCO3)) — metamorphic

Zebra Marble

Metamorphosed Alabaster/Limestone (CaCO3)

Quartzite (Quartzite (primarily SiO₂)) — metamorphic

Quartzite

Quartzite (primarily SiO₂)

Botryoidal Hematite (Kidney Ore) (Hematite (Fe2O3)) — Mineral

Botryoidal Hematite (Kidney Ore)

Hematite (Fe2O3)

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)

Rose Quartz (Rose Quartz (SiO2)) — mineral

Rose Quartz

Rose Quartz (SiO2)

Ambergris (Physeter macrocephalus excreta (Ambergris)) — mineraloid / organic geological find

Ambergris

Physeter macrocephalus excreta (Ambergris)

mineraloid / organic geological find