Rock Identifier

Category

Organic (Geological Relative)

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

Shale or Argillite (Shale (fine-grained clastic sedimentary rock) or Argillite (low-grade metamorphic rock derived from shale)) — Sedimentary or Metamorphic (low grade)

Shale or Argillite

Shale (fine-grained clastic sedimentary rock) or Argillite (low-grade metamorphic rock derived from shale)

Sedimentary or Metamorphic (low grade)

Baroque Pearl (and potentially a small Sapphire/Blue Topaz) (Pearl: Calcium Carbonate (aragonite or calcite) with conchiolin. Sapphire: Aluminum Oxide (Al2O3). Blue Topaz: Al2SiO4(F,OH)2.) — Organic Gemstone (for pearl), Mineral (for sapphire/topaz)

Baroque Pearl (and potentially a small Sapphire/Blue Topaz)

Pearl: Calcium Carbonate (aragonite or calcite) with conchiolin. Sapphire: Aluminum Oxide (Al2O3). Blue Topaz: Al2SiO4(F,OH)2.

Organic Gemstone (for pearl), Mineral (for sapphire/topaz)

Chalcedony Geode (Chalcedony (SiO2) within a geode structure) — Mineral Geode/Sedimentary or Volcanic related

Chalcedony Geode

Chalcedony (SiO2) within a geode structure

Mineral Geode/Sedimentary or Volcanic related

Coral (Precious Coral) (Corallium rubrum (Red Coral), Paracorallium japonicum (Momo Coral), Pleurocorallium elatius (Sardinian Coral), various other species within the Corallidae family. Chemically, it's primarily Calcium Carbonate (CaCO
3
).) — Mineral, Organic Gemstone

Coral (Precious Coral)

Corallium rubrum (Red Coral), Paracorallium japonicum (Momo Coral), Pleurocorallium elatius (Sardinian Coral), various other species within the Corallidae family. Chemically, it's primarily Calcium Carbonate (CaCO 3 ).

Mineral, Organic Gemstone

Ambergris (Sea Wax) (Physeter macrocephalus fecalith) — Organic geological/oceanic specimen

Ambergris (Sea Wax)

Physeter macrocephalus fecalith

Organic geological/oceanic specimen

Shale (possibly) (Shale (fine-grained clastic sedimentary rock)) — sedimentary

Shale (possibly)

Shale (fine-grained clastic sedimentary rock)

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)

Coal (Anthracite or Bituminous Coal) — sedimentary

Coal

Anthracite or Bituminous Coal

Flower Agate (Plume Agate) (Chalcedony (Silicon Dioxide) with Spherulitic Inclusions - SiO2) — mineral

Flower Agate (Plume Agate)

Chalcedony (Silicon Dioxide) with Spherulitic Inclusions - SiO2

Coquina (Biogenic Limestone (Calcium Carbonate - CaCO3)) — sedimentary

Coquina

Biogenic Limestone (Calcium Carbonate - CaCO3)

Lignite (Brown Coal) (Humic Lignite (Carbonaceous sedimentary rock)) — sedimentary

Lignite (Brown Coal)

Humic Lignite (Carbonaceous sedimentary rock)

Obsidian (Amorphous volcanic glass (70-75% SiO2)) — igneous

Obsidian

Amorphous volcanic glass (70-75% SiO2)

Desert Rose (Gelenite) (Gypsum (Calcium Sulfate Dihydrate, CaSO4·2H2O)) — mineral

Desert Rose (Gelenite)

Gypsum (Calcium Sulfate Dihydrate, CaSO4·2H2O)

Lazulite Quartzite (Quartzite with Lazulite (SiO2 with (Mg,Fe)Al2(PO4)2(OH)2)) — metamorphic

Lazulite Quartzite

Quartzite with Lazulite (SiO2 with (Mg,Fe)Al2(PO4)2(OH)2)

Orange Calcite (Calcite (CaCO3)) — Mineral

Orange Calcite

Calcite (CaCO3)

Orbicular Gabbro (Orbicular Gabbro) — igneous

Orbicular Gabbro

Orbicular Gabbro

Chert (often called Flint when dark) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (often called Flint when dark)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Flower Agate (Chalcedony (SiO2) with Opaque Spherulitic Inclusions) — mineral

Flower Agate

Chalcedony (SiO2) with Opaque Spherulitic Inclusions

Flower Agate (Cherry Blossom Agate) (Chalcedony (Silicon Dioxide) with Opaque Inclusions - SiO2) — mineral

Flower Agate (Cherry Blossom Agate)

Chalcedony (Silicon Dioxide) with Opaque Inclusions - SiO2

Coquina (Coquina (Bioclastic Limestone)) — sedimentary

Coquina

Coquina (Bioclastic Limestone)

Obsidian (Obsidian (Volcanic Glass)) — igneous

Obsidian

Obsidian (Volcanic Glass)

Fossil Shark Tooth (Carcharadon sp. (likely Carcharodon carcharias or similar Lamniformes)) — fossil

Fossil Shark Tooth

Carcharadon sp. (likely Carcharodon carcharias or similar Lamniformes)

Bumble Bee Jasper (Calcite and Volcanic Ash Mixture) — sedimentary

Bumble Bee Jasper

Calcite and Volcanic Ash Mixture

Obsidian (Obsidian (Volcanic Glass)) — igneous

Obsidian

Obsidian (Volcanic Glass)

Obsidian (Obsidian (Volcanic Glass)) — igneous

Obsidian

Obsidian (Volcanic Glass)

Granite (Micro-specimen) (Plutonic Igneous Rock (primarily Quartz, Feldspar, and Mica)) — igneous

Granite (Micro-specimen)

Plutonic Igneous Rock (primarily Quartz, Feldspar, and Mica)

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

Quartz (Milky Quartz)

Silicon Dioxide (SiO2)

Green Chalcedony (likely Chrysoprase or dyed Green Agate) (Silicon Dioxide (SiO2) with nickel impurities or chromium/dye) — mineral

Green Chalcedony (likely Chrysoprase or dyed Green Agate)

Silicon Dioxide (SiO2) with nickel impurities or chromium/dye

Polished Black Obsidian (Volcanic Glass (70-75% SiO2)) — igneous

Polished Black Obsidian

Volcanic Glass (70-75% SiO2)

Obsidian (Volcanic Glass (SiO2 rich)) — igneous

Obsidian

Volcanic Glass (SiO2 rich)

Bumble Bee Jasper (Volcanic Tuff (mixture of SiO2, CaCo3, S, and As2S3)) — igneous

Bumble Bee Jasper

Volcanic Tuff (mixture of SiO2, CaCo3, S, and As2S3)

Jadeite Bangle (NaAl(Si2O6)) — gemstone

Jadeite Bangle

NaAl(Si2O6)

Coquina (Biogenic Limestone (Calcium Carbonate, CaCO3)) — sedimentary

Coquina

Biogenic Limestone (Calcium Carbonate, CaCO3)

Obsidian (Obsidian (Volcanic Glass)) — igneous

Obsidian

Obsidian (Volcanic Glass)

Chert (Field Stone) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (Field Stone)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Clear Quartz (Silicon Dioxide (SiO2)) — mineral

Clear Quartz

Silicon Dioxide (SiO2)

Obsidian (Volcanic Glass (SiO2 + impurities)) — igneous

Obsidian

Volcanic Glass (SiO2 + impurities)

Banded Calcite (often sold as 'Green Onyx') (Calcite (Calcium Carbonate, CaCO3)) — sedimentary

Banded Calcite (often sold as 'Green Onyx')

Calcite (Calcium Carbonate, CaCO3)

Greenstone (Epidosite / Chlorite Schist) (Metabasalt (often contains Epidote Ca2Al2(Fe3+,Al)(SiO4)(Si2O7)O(OH) or Chlorite)) — metamorphic

Greenstone (Epidosite / Chlorite Schist)

Metabasalt (often contains Epidote Ca2Al2(Fe3+,Al)(SiO4)(Si2O7)O(OH) or Chlorite)

Granite (Phaneritic Plutonic Felsic Rock (SiO2, KAlSi3O8, NaAlSi3O8, CaAl2Si2O8)) — igneous

Granite

Phaneritic Plutonic Felsic Rock (SiO2, KAlSi3O8, NaAlSi3O8, CaAl2Si2O8)

Obsidian (Amorphous volcanic glass (SiO2)) — igneous

Obsidian

Amorphous volcanic glass (SiO2)

Obsidian (Volcanic Glass (SiO2)) — igneous

Obsidian

Volcanic Glass (SiO2)