Limestone (specifically Carboniferous Limestone)
Calcium Carbonate (CaCO3)
sedimentary
Category
Marble
Browse marble specimens identified by the Rock Identifier community.
Fossilized Shark Tooth (Cretaceous to Neogene)
Elasmobranchii dental fossil (likely Squalicorax or similar species)
mineral (biogenic replacement)
Pearl
Calcium Carbonate (primarily Aragonite and Calcite), CaCO3
mineral
Chert with Quartz Veining
Silicon Dioxide (SiO2)
sedimentary
Limestone
Calcium Carbonate (CaCO3)
sedimentary
Aragonite Star Cluster
Aragonite (Calcium Carbonate, CaCO3)
mineral
Fossiliferous Limestone (Crinoidal)
Calcium Carbonate (CaCO3) - Limestone containing bioclasts
sedimentary
Pyrite Concretion
Iron Sulfide (FeS2) in Sedimentary Matrix
sedimentary
Fossilized Coral (Favosites)
Favosites goldfussi / Tabulata
sedimentary
Natural or Cultured Pearl
Calcium Carbonate (Aragonite and Conchiolin), CaCO3
Mineral (Organic)
Chert (variations include Flint)
Microcrystalline or cryptocrystalline Quartz (SiO2)
sedimentary
Sandstone
Arenite (specifically Quartz Arenite)
sedimentary
Limestone
Sedimentary Calcium Carbonate (CaCO3)
sedimentary
Piddock bored rock (Boring Stone)
Ichnofossil-bearing Limestone or Mudstone (trace fossils by Pholadidae)
sedimentary
Fossiliferous Limestone
Biogenic Limestone (Calcium Carbonate, CaCO3)
sedimentary
Fossiliferous Limestone
Fossiliferous Calcite (CaCO3)
sedimentary
Chalk
Calcium Carbonate (CaCO3)
sedimentary
Limestone (Weathered)
Sedimentary Carbonate Rock (CaCO3)
sedimentary
Limestone
Calcium Carbonate (CaCO3)
sedimentary
Spinifex Textured Komatiite
Ultramafic Komatiite (with Olivine Spinifex)
igneous
Olivine (Peridot)
Magnesium Iron Silicate (Mg, Fe)2SiO4
mineral
Green Druzy Quartz (Prasiolite)
Silicon Dioxide (SiO2) with inclusions (typically Chlorite or Actinolite)
mineral
Sandstone
Arenite
sedimentary
Chalk (Sedimentary Limestone)
Calcite (CaCO3)
sedimentary
Limestone
Calcium carbonate (CaCO3)
sedimentary
Sandstone with Iron Staining
Clastic sedimentary rock (primarily SiO2 with Fe2O3)
sedimentary
Sandstone (with potential mineral inclusions)
Clastic sedimentary rock (primarily Quartz, SiO2)
sedimentary
Sandstone
Arenite (primarily SiO2)
sedimentary
Fossilized Gastropod Internal Mold
Steinkern (Mollusca: Gastropoda)
sedimentary
Limestone
Calcium Carbonate (CaCO3)
sedimentary
Limestone
Calcium Carbonate (CaCO3)
sedimentary
Graywacke
Lithic Sandstone (Graywacke)
sedimentary
Fossilized Horn Coral
Rugosa
fossil
Stromatolite
Biogenic Sedimentary Rock (composed predominantly of CaCO3)
sedimentary
Chert (specifically Jasper)
Silicon dioxide (SiO2) with iron oxide inclusions
sedimentary
Chert (varieties include Flint and Jasper)
Silicon Dioxide (SiO2)
sedimentary
Belemnoit Fossil (Sea Squid Fossil)
Belemnitida (Order within Cephalopoda)
sedimentary
Chert Nodule (Fossiliferous Chert)
Microcrystalline Quartz (SiO2)
sedimentary
Limestone
Calcium Carbonate (CaCO3)
sedimentary
Ammonite Fossil
Ammonoidea (Calcium carbonate - CaCO3)
sedimentary
Limestone
Calcium Carbonate (CaCO3)
sedimentary
Pearl
Biogenic Calcium Carbonate (Aragonite/Calcite), CaCO3
mineral