Rock Identifier

Category

Organic Gemstone (Fossilized Resin)

Browse organic gemstone (fossilized resin) specimens identified by the Rock Identifier community.

Chert / Flint (Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert / Flint

Cryptocrystalline Quartz (SiO2)

Black Limestone with Calcite Veining (Bituminous Limestone (CaCO3 with Organic Carbon inclusions)) — sedimentary

Black Limestone with Calcite Veining

Bituminous Limestone (CaCO3 with Organic Carbon inclusions)

Orthoceras Fossil in Limestone (Orthoceras (extinct genus of cephalopods), mineralized as Calcite (CaCO3) in Fossiliferous Limestone) — sedimentary

Orthoceras Fossil in Limestone

Orthoceras (extinct genus of cephalopods), mineralized as Calcite (CaCO3) in Fossiliferous Limestone

Fossiliferous Sandstone (with Brachiopod or Bivalve mold) (Clastic Sedimentary Rock with Macrofossil Mold) — sedimentary

Fossiliferous Sandstone (with Brachiopod or Bivalve mold)

Clastic Sedimentary Rock with Macrofossil Mold

Sandstone (Sandstone (various mineral compositions)) — Sedimentary

Sandstone

Sandstone (various mineral compositions)

Chert (and Chalcedony) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (and Chalcedony)

Microcrystalline Quartz (SiO2)

Chert (Jasper variety) (Silicon Dioxide (SiO2)) — sedimentary

Chert (Jasper variety)

Silicon Dioxide (SiO2)

Chert (specifically Flint or Jasper variant) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (specifically Flint or Jasper variant)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert (Cherty Flint/Jasper variety) (Microcrystalline or cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (Cherty Flint/Jasper variety)

Microcrystalline or cryptocrystalline Quartz (SiO2)

Pyrite (Pyrite (Iron sulfide, FeS₂)) — Mineral

Pyrite

Pyrite (Iron sulfide, FeS₂)

Crinoid Stem Fossil (Class Crinoidea (Phylum Echinodermata), primarily Calcium Carbonate (CaCO3)) — sedimentary

Crinoid Stem Fossil

Class Crinoidea (Phylum Echinodermata), primarily Calcium Carbonate (CaCO3)

Kidney Stone (Calcium Oxalate (CaC2O4), Uric Acid, or Struvite) — mineral

Kidney Stone

Calcium Oxalate (CaC2O4), Uric Acid, or Struvite

Fossilized Shark Tooth (Otodus obliquus) (Otodus obliquus (composed primarily of Fluorapatite)) — mineral

Fossilized Shark Tooth (Otodus obliquus)

Otodus obliquus (composed primarily of Fluorapatite)

Chert (Jasper variation) (Chert (SiO2)) — sedimentary

Chert (Jasper variation)

Chert (SiO2)

Mother of Pearl (Nacre) (Calcium Carbonate (primarily aragonite, with conchiolin)) — Organic Gemstone/Biomineral

Mother of Pearl (Nacre)

Calcium Carbonate (primarily aragonite, with conchiolin)

Organic Gemstone/Biomineral

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

Fossilized Shark Tooth (Dermal Denticle or worn tooth fragment) (Elasmobranchii (fossil remains)) — sedimentary

Fossilized Shark Tooth (Dermal Denticle or worn tooth fragment)

Elasmobranchii (fossil remains)

Druzy Chalcedony/Quartz on Fluorite core (Silicon Dioxide (SiO2) on Calcium Fluoride (CaF2)) — mineral

Druzy Chalcedony/Quartz on Fluorite core

Silicon Dioxide (SiO2) on Calcium Fluoride (CaF2)

Fossilized Rugose Coral (Horn Coral) (Order Rugosa (extinct tetra-coral)) — sedimentary

Fossilized Rugose Coral (Horn Coral)

Order Rugosa (extinct tetra-coral)

Fossilized Shark Tooth (Otodus obliquus) (Otodus obliquus (Mineral composition: Bio-apatite/Calcium Phosphate replaced by various minerals)) — sedimentary (fossil)

Fossilized Shark Tooth (Otodus obliquus)

Otodus obliquus (Mineral composition: Bio-apatite/Calcium Phosphate replaced by various minerals)

sedimentary (fossil)

Banded Chert (Cryptocrystalline Quartz (SiO2)) — sedimentary

Banded Chert

Cryptocrystalline Quartz (SiO2)

Cockle Shell (Fossil or Recent) (Class Bivalvia, Family Cardiidae (e.g., Cerastoderma edule for common cockle)) — Sedimentary (Biogenic, a type of fossil)

Cockle Shell (Fossil or Recent)

Class Bivalvia, Family Cardiidae (e.g., Cerastoderma edule for common cockle)

Sedimentary (Biogenic, a type of fossil)

Pearl (Calcium Carbonate (Aragonite or Calcite) and Conchiolin) — Mineraloid

Pearl

Calcium Carbonate (Aragonite or Calcite) and Conchiolin

Potassium-Rich Silicate Clay (inferred from biological context) (Phyllosilicate group (likely Illite or Smectite within surrounding soil substrate)) — mineral

Potassium-Rich Silicate Clay (inferred from biological context)

Phyllosilicate group (likely Illite or Smectite within surrounding soil substrate)

Pearl (Imitation or Cultured) (Calcium Carbonate (Aragonite/Calcite) - CaCO3) — Mineraloid (Organic)

Pearl (Imitation or Cultured)

Calcium Carbonate (Aragonite/Calcite) - CaCO3

Mineraloid (Organic)

Grass (Organic Matter/Soil) (Poaceae (family of monocotyledonous flowering plants)) — Organic Materia (Not a rock or mineral)

Grass (Organic Matter/Soil)

Poaceae (family of monocotyledonous flowering plants)

Organic Materia (Not a rock or mineral)

Fossilized Solitary Rugose Coral (Horn Coral) (Order: Rugosa (e.g., Grewingkia or Heliophyllum); composed of Calcite (CaCO3) or Silica (SiO2)) — sedimentary

Fossilized Solitary Rugose Coral (Horn Coral)

Order: Rugosa (e.g., Grewingkia or Heliophyllum); composed of Calcite (CaCO3) or Silica (SiO2)

Mookaite Jasper (Siliceous sedimentary rock (variety of Jasper/Chert)) — Sedimentary Rock

Mookaite Jasper

Siliceous sedimentary rock (variety of Jasper/Chert)

Sedimentary Rock

Fossiliferous Limestone with Rugose Coral (Lithostrotionella (Limestone Matrix - CaCO3)) — sedimentary

Fossiliferous Limestone with Rugose Coral

Lithostrotionella (Limestone Matrix - CaCO3)

Manganese-coated Sandstone (Clastic sedimentary rock with Manganese Oxide (often Pyrolusite or Psilomelane)) — sedimentary

Manganese-coated Sandstone

Clastic sedimentary rock with Manganese Oxide (often Pyrolusite or Psilomelane)

Fossiliferous Limestone with Brachiopods (Calcium Carbonate (CaCO3) with fossilized Brachiopoda sp. (likely Order Spiriferida or Rhynchonellida)) — sedimentary

Fossiliferous Limestone with Brachiopods

Calcium Carbonate (CaCO3) with fossilized Brachiopoda sp. (likely Order Spiriferida or Rhynchonellida)

Paper (Cellulose) (Cellulose (C6H10O5)n) — Organic (Anthropogenic)

Paper (Cellulose)

Cellulose (C6H10O5)n

Organic (Anthropogenic)

Pyrite (Pyrite (FeS2)) — Mineral

Pyrite

Pyrite (FeS2)

Fossiliferous Limestone (Shell Fragment) (Biogenic Limestone (Calcium Carbonate / CaCO3)) — sedimentary

Fossiliferous Limestone (Shell Fragment)

Biogenic Limestone (Calcium Carbonate / CaCO3)

Fossil Shark Tooth (Sand Tiger or Mackerel Shark) (Carcharias sp. or Otodus sp. replaced by Hydroxylapatite/Calcium Carbonate) — sedimentary

Fossil Shark Tooth (Sand Tiger or Mackerel Shark)

Carcharias sp. or Otodus sp. replaced by Hydroxylapatite/Calcium Carbonate

Fossiliferous Limestone (Fossiliferous Limestone) — sedimentary

Fossiliferous Limestone

Fossiliferous Limestone

Fossiliferous Limestone (Fossiliferous Limestone (CaCO3)) — sedimentary

Fossiliferous Limestone

Fossiliferous Limestone (CaCO3)

Coquina / Limonite-stained Limestone (Sedimentary Limestone with Iron Oxyhydroxide (FeO(OH)·nH2O)) — sedimentary

Coquina / Limonite-stained Limestone

Sedimentary Limestone with Iron Oxyhydroxide (FeO(OH)·nH2O)

Onyx (Black) and Mother of Pearl Inlay (Silicon Dioxide (SiO2) for Onyx; Aragonite (CaCO3) for Mother of Pearl) — mineral

Onyx (Black) and Mother of Pearl Inlay

Silicon Dioxide (SiO2) for Onyx; Aragonite (CaCO3) for Mother of Pearl

Stardust (Micrometeorite) (Chondrite / Micrometeorite (Extraterrestrial Silicate)) — igneous

Stardust (Micrometeorite)

Chondrite / Micrometeorite (Extraterrestrial Silicate)

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

Moss Agate

Chalcedony (SiO2) with inclusions of hornblende or chlorite

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

Moss Agate

Chalcedony (SiO2) with inclusions of manganese or iron oxides