Sandstone (likely Arkose or Quartz Sandstone)
Arenite (SiO2 principal component)
Category
Browse organic (zoogenic) specimens identified by the Rock Identifier community.
Sandstone (likely Arkose or Quartz Sandstone)
Arenite (SiO2 principal component)
Red Chert (Jasper)
Silicon Dioxide (SiO2)
Chert (specifically Banded Chert)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (and Flint)
Silicon Dioxide (SiO2)
Fossil Coral (Rugosa or Solitary Coral)
Rugosa (Order), often referred to as 'Horn Coral' (Lithostrotionella or Grewingkia)
Chert (Holey Stone)
Microcrystalline Quartz (SiO2)
Amber
Succinite (Carbon-based organic compound; approximate formula C10H16O)
Ironstone Concretion (Ironstone Gourd)
Limonite/Goethite Concretion (FeOO(H))
Pink Opal
Hydrated silicon dioxide (SiO2·nH2O) with inclusions
Chert (Nodule)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Limestone
Calcium Carbonate (CaCO3)
Moss Agate
Silicon Dioxide with inclusions (SiO2 + impurities)
Amber / Copal
Succinite (fossilized resin)
Shale or Siltstone
Sedimentary Clastic Rock (Variable mineral composition including quartz and clay minerals)
Moss Agate
Silicon Dioxide (SiO2) with inclusions of Manganese or Iron oxide
Chert (Brecciated Chert)
Silicon Dioxide (SiO2)
Fossilized Sand Tiger Shark Tooth
Carcharias taurus / Striatolamia macrota (mineralized as Hydroxylapatite/Francolite)
Dendritic Agate / Moss Agate
Silicon Dioxide (SiO2) with Manganese/Iron oxide inclusions
Amber
Succinite (specifically for Baltic amber); Approximate formula: C10H16O
Green Moss Agate
Silicon Dioxide (SiO2) with inclusions of hornblende or chlorite
Moss Agate
Silicon Dioxide (SiO2) with inclusions of hornblende or chlorite
Moss Agate
Chalcedony (Silicon Dioxide, SiO2) with dendritic inclusions
Shale
Clastic sedimentary rock (primarily clay and silt minerals)
Pearl
Pearl (Calcium Carbonate with organic conchiolin, CaCO3)
Amber (Cherry or Red variety)
Succinite (with various trace amounts of organic compounds)
Bituminous Coal
Organic-rich sedimentary rock (Complex hydrocarbons)
Red Amber (Burmite/Cherry Amber)
Succinite / Retinite (Organic Fossilized Resin, C10H16O)
Black Pearl (Tahitian or Irradiated Type)
Organic gemstone (Calcium Carbonate with Conchiolin Binding)
Blue Agate (Tumbled and Dyed)
Silicon Dioxide (SiO2) with likely organic dyes
Fossiliferous Limestone (Crinoidal)
Calcite-bearing bioclastic packstone (CaCO3)
Chert (Jasper-like Silicate)
Microcrystalline quartz (SiO2)
Petrified Wood
Silicified wood (Quartz/Chalcedony - SiO2)
Chert (specifically Flint or Gray Chert)
Silicon Dioxide (SiO2)
Chert (Yellow Chert/Flint)
Silicon Dioxide (SiO2)
Chert (Flint)
Microcrystalline Quartz (SiO2)
Chert (Yellow Jasper variant)
Microcrystalline Quartz (SiO2)
Chert (River Pebble)
Microcrystalline Quartz (SiO2)
Chert (and/or Chalcedony)
Microcrystalline Silica (SiO2)
Chert (and Quartz Gravel)
Chert (Cryptocrystalline Quartz, SiO2)
Chert (Yellow/Tan Variety)
Chert (SiO2)
Chert (specifically Tan/Yellow Chert)
Silicon Dioxide (SiO2)
Fossiliferous Limestone
Calcite-rich Sedimentary Rock (CaCO3)