Chert (Gravel)
Chert (Microcrystalline Silicon Dioxide, SiO2)
Category
Browse sedimentary (fossil) specimens identified by the Rock Identifier community.
Chert (Gravel)
Chert (Microcrystalline Silicon Dioxide, SiO2)
Weathered sandstone or iron-rich sedimentary cobble
Quartz arenite to ferruginous sandstone; predominantly SiO₂ (quartz) with iron-oxide cement
Weathered sandstone or iron-stained sedimentary rock
Likely quartz-rich sandstone; exact identification is uncertain from the photograph
Weathered sandstone pebble
Quartz-rich sandstone, likely ferruginous sandstone
Limestone
Calcium Carbonate (CaCO3)
Limestone
Sedimentary rock primarily composed of Calcite (CaCO3)
Limestone
Calcium Carbonate (CaCO3)
Sandstone
Arenite (SiO2 primarily)
Sandstone
Arenite (SiO2 primarily)
Sandstone (with Iron Staining)
Clastic sedimentary rock (primarily Quartz with Fe2O3 staining)
Fossilized Crinoid Stem in Pebble
Crinoidea (Class) preserved in calcite/matrix
Coral Rock (Coquina)
Biogenic Limestone (Calcium Carbonate - CaCO3)
Sandstone (Ferruginous)
Arenite (composed primarily of SiO2 with Fe2O3 cement)
Limestone
Sedimentary rock composed primarily of Calcium Carbonate (CaCO3)
Crinoid Stem Fossil
Crinoid columnal (Echinodermata)
Fossil Shark Tooth
Chondrichthyes (Class)
Limestone
Sedimentary rock composed primarily of calcium carbonate (CaCO3)
Limestone pebble
Sedimentary rock composed mainly of calcium carbonate (CaCO3)
Ironstone concretion
Siderite or Limonite-rich Concretion (FeO(OH)·nH2O)
Ironstone Concretion
Ferruginous Concretion
Black Shale
Argillaceous Chert/Shale
Dendritic Siltstone (or Mudstone)
Siltstone with Manganese Oxide dendrites
Sandstone Concretion
Sandstone (Sedimentary rock, mostly SiO2)
Ironstone Concretion
Siderite or Limonite Concretion
Siltstone with iron staining
Siltstone (primarily SiO2 with FeO(OH) coatings)
Fossilized Shark Tooth
Chondrichthyes (Class) - likely Carcharodon or Otodus genus
Shark Tooth Fossil
Elasmobranchii fossil (likely Carcharias or Odontaspis sp.)
Petrified Wood
Silicified Wood (SiO2)
Sandstone (with Concretion)
Arenite / Quartzose Sandstone
Crushed Limestone
Calcium Carbonate (CaCO3)
Limestone (Buff/Tan)
Calcium Carbonate (CaCO3)
Sandstone
Arenite (SiO2 principal)
Shale (possibly Carbonaceous or Oil Shale)
Argillaceous Sedimentary Rock
Limestone
Sedimentary rock composed of Calcium Carbonate (CaCO3)
Sandstone
Sandstone (clastic sedimentary rock), primarily SiO2
Mudstone/Siltstone with Liesegang Bands
Argillaceous Sedimentary Rock with Chemical Banding
Sandstone
Arenite (SiO2 principal component)
Limestone
Calcium Carbonate (CaCO3)
Dendritic Jasper
Silicon Dioxide (SiO2) with Manganese/Iron oxide inclusions
Sandstone
Arenite (Silicon Dioxide, SiO2 based)
Sandstone Concretion
Sedimentary Concretion (SiO2 or CaCO3 cemented)
Chert (Jasper/Agate variety)
Microcrystalline Quartz (SiO2)