Tumbled chalcedony (likely moss or dendritic agate)
Microcrystalline quartz, SiO₂, with iron-oxide inclusions
Category
Browse organic (anthropogenic) specimens identified by the Rock Identifier community.
Tumbled chalcedony (likely moss or dendritic agate)
Microcrystalline quartz, SiO₂, with iron-oxide inclusions
Limestone Pebble
Sedimentary carbonate rock (CaCO3)
Amber
Succinite (fossilized tree resin)
Amber (and Cubic Zirconia)
Fossilized Tree Resin
Moss Agate
Silicon dioxide (SiO2) with inclusions
Manganese-coated Sandstone
Clastic sedimentary rock with Manganese Oxide (often Pyrolusite or Psilomelane)
Fossiliferous Limestone with Rugose Coral
Lithostrotionella (Limestone Matrix - CaCO3)
Knightia Fossil in Limestone
Knightia eocaena in micritic limestone
Limestone
Calcium Carbonate (CaCO3)
Shark Tooth Fossil
Carcharhiniformes or Lamniformes (order level fossil)
Petrified Wood
Silicified wood (SiO2)
Amber
Succinite
Amber
Succinite
Fossil Shark Tooth (Sand Tiger or Mackerel Shark)
Carcharias sp. or Otodus sp. replaced by Hydroxylapatite/Calcium Carbonate
Amethyst, Aquamarine, and Pearl Ring
SiO2 (Amethyst), Be3Al2Si6O18 (Aquamarine), CaCO3 (Pearl)
Fossiliferous Flint
Microcrystalline Quartz (SiO2) with Echinoid Fossil
Amber
Succinate (Fossilized Tree Resin)
Amber
Succinite (Fossilized Resin)
Sandstone Concretion
Limonitic Sandstone Concretion
Amber
Succinite (Fossilized Resin)
Amber
Succinite (amorphous organic polymer)
Pearl
Organic Mineraloid (CaCO3 + Conchiolin)
Rough Amber (likely Copal or immature Amber)
Organic gemstone / Succinite (if Baltic)
Amber
Succinicum (Organic Gemstone - Resinite)
Amber
Amber (Amorphous Organic Hydrocarbon)
Amber
Succinate (Organic Fossilized Resin)
Amber
Succinite (a fossilized organic resin)
Coal (most likely Bituminous or Anthracite)
Coal (organic sedimentary rock)
Fossil Bivalve / Ostreid Shell (Hag Stone / Perforated Pebble)
Phylum Mollusca, Class Bivalvia
Amber
Succinite (C10H16O)
Coal (Bituminous or Anthracite)
Carbonaceous sedimentary rock (primarily Carbon, C)
Limestone with Fossil Inclusion
Sedimentary Calcium Carbonate (CaCO3)
Megalodon Shark Tooth (Partial Fossil)
Otodus megalodon (fossilized in Calcium Phosphate/Apatite)
Natural Pearl (appearing in a jewelry setting)
Calcium Carbonate (mostly Aragonite), CaCO3 with Conchiolin
Fossilized Shell in Limestone
Bivalve fossil (CaCO3) in Carbonate Sedimentary Rock
Pearl
Calcium carbonate (Aragonite/Calcite) - CaCO3
Fossilized Shark Tooth or Bone Fragment
Vertebrate Fossil (likely Carcharodon or similar genus)
Fossiliferous Limestone
Limestone (Calcium Carbonate - CaCO3)
Fossiliferous Limestone
Fossiliferous Limestone (CaCO3)
Limestone (with possible Crinoid or Fossil Impression)
Calcium Carbonate (CaCO3) / Calcite
Limestone
Calcium Carbonate (CaCO3)
Limestone
Calcium Carbonate (CaCO3)