Sandstone (with Moss)
Quartz Arenite / Sandstone
Category
Browse organic material specimens identified by the Rock Identifier community.
Sandstone (with Moss)
Quartz Arenite / Sandstone
Pyrite
Iron Sulfide (FeS2)
Jasper
Microcrystalline Quartz (SiO2)
Pyrite Geode
Iron Disulfide (FeS2)
Tufa (Calcareous Tufa)
Calcareous Tufa (Precipitated CaCO3)
Polished moss agate cabochon
Chalcedony (microcrystalline quartz, SiO₂) with chlorite/iron-oxide inclusions
Petrified Wood
Silicified Wood (SiO2)
Tonsil Stone (Tonsillolith)
Calcium phosphate / Calcium carbonate biomineral
Jasper
Chalcedony (SiO2)
Agatized or Silicified Fossil/Coral, or Jasper
SiO2
Fossil Shark Tooth
Otodus sp. or Carcharocles sp. (likely fossilized Chondrichthyes)
Jasper
Silicon dioxide (Quartz variety), SiO2
Chert (or Chalcedony)
Microcrystalline Quartz (SiO2)
Chert (Chalcedony/Common Opal)
Microcrystalline Quartz (SiO2)
Jasper Agate
Silicon dioxide (SiO2)
Pyrite (Fool's Gold) Cube
Iron Sulfide (FeS2)
Tumbled brown agate (likely moss or plume agate)
Microcrystalline quartz, chiefly chalcedony (SiO₂), with iron-oxide and possibly mineral inclusions
Tumbled yellow calcite
Calcite (CaCO₃), likely honey or lemon calcite
Fossiliferous Limestone
Calcium Carbonate (CaCO3) with Bioclasts
Chert Nodule / Flint
Microcrystalline Quartz (SiO2)
Polished/tumbled calcite
Calcite (calcium carbonate, CaCO₃)
Basaltic Tuff / Volcanic Breccia
Pyroclastic Breccia / Lithic Tuff
Fossilized Bone
Permineralized Vertebrate Bone
Jasper
Microcrystalline Quartz (SiO2)
Jasper
Silicon dioxide (SiO2) microcrystalline quartz
Chert (Flint)
Cryptocrystalline Quartz (SiO2)
Jasper
Silicon dioxide (SiO2) with impurities, microcrystalline quartz
Jasper
Microcrystalline Quartz (SiO2)
Mammoth Molar Fossil
Mammuthus primigenius (Tooth fragment)
Chert Nodules in Limestone
Microcrystalline Quartz (SiO2) within Calcium Carbonate (CaCO3)
Polished septarian nodule
Septarian concretion, commonly calcite/aragonite with brown calcite or barite veins in a limestone–clay matrix
Petrified Wood
Silicified Wood (primarily SiO2)
Fossilized Shark Tooth
Chondrichthyes (Class) fossilized dentition
Fossil Shark Tooth
Chondrichthyes (Class)
Jasper
Silicon Dioxide (Microcrystalline Quartz)
Poppy Jasper
Microcrystalline Quartz (SiO2) with hematite and other inclusions
Jasper
Silicon Dioxide (SiO2) with impurities
Sandstone
Arenite (SiO2 composed primarily of quartz)
Chert / Flint
Silicon dioxide (SiO2)
Chert (Yellow Jasper variant)
Silicon Dioxide (SiO2)
Jasper
Silicon Dioxide (Microcrystalline Quartz, SiO2)
Jasper
Silicon dioxide (Microcrystalline Quartz, SiO2)