Granitic Gneiss
Gneiss (containing Potassium Feldspar and Quartz)
Category
Browse rock (likely sedimentary) specimens identified by the Rock Identifier community.
Granitic Gneiss
Gneiss (containing Potassium Feldspar and Quartz)
Sandstone Concretion
Arenaceous concretion (primarily SiO2 with Fe2O3 staining)
Fossil Crab
Decapoda (likely Avitelmessus or Raninidae family)
Sandstone
Arenite (primarily SiO2)
River Pebble (Gravel)
Clastic sedimentary rock (likely Siltstone or Mudstone pebble; SiO2 with various impurities)
Quartz Geode
Quartz (Silicon Dioxide - SiO2) within a Chalcedony and Limonite shell
Chert (Iron-stained)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Banded Gneiss
Gneiss (complex metamorphic silicate rock)
Sandstone (Green/Yellow Siltstone variant)
Arenite or Siltstone (primarily SiO2 with mineral staining)
Sandstone (with biological crust)
Arenite (SiO2 based)
Sandstone (with potentially metamorphic or basaltic bands)
Arenite / Lithic Wacke
Unidentified Rock Fragment
Unknown
Sandstone (likely Graywacke or Lithic Sandstone)
Clastic Sedimentary Rock
River Rock (likely Siltstone or fine-grained Sandstone)
Clastic Sedimentary Rock
Chert (specifically Jasper)
Silicon dioxide (SiO2) with iron oxide inclusions
Sandstone (likely with Borings or Vesicular Basalt)
Clastic Sedimentary Rock (Sandstone)
Sandstone
Clastic Sedimentary Rock (composed mostly of quartz, SiO2)
Sandstone
Arenite (composed primarily of SiO2)
Sandstone
Arenite (SiO2 based with mineral cement)
Sandstone (Quartz-rich)
Sandstone (SiO2 dominated)
Sandstone (Greywacke)
Arenite / Wacke (Mainly SiO2 with various lithic fragments)
Sandstone (Graywacke type)
Clastic Sedimentary Rock (Lithic Sandstone)
Sandstone with Magnetite and Iron Staining
Clastic Sedimentary Rock (contains Fe3O4 and Limonite/Hematite)
Garnet (Almandine)
Almandine, Fe3Al2(SiO4)3
Sandstone (specifically Flagstone)
Arenite (primarily composed of SiO2)
Vesicular Sandstone
Clastic Sedimentary Rock (Sandstone)
Sandstone (likely Fossiliferous Sandstone)
Clastic sedimentary rock (primarily SiO2)
Sandstone (likely Ferruginous)
Sandstone (SiO2 with iron oxides)
Quartz (Iron-Stained)
Silicon Dioxide (SiO2)
Blue Chalcedony
Chalcedony (Silicon Dioxide, SiO2)
Chert (and/or Siltstone River Pebble)
Silicon Dioxide (SiO2) - Microcrystalline Quartz
Yellow Quartz (Chalcedony or Agate)
Silicon Dioxide (SiO2)
Quartz Geode / Druzy Quartz
Silicon Dioxide (SiO2)
Sandstone (Water-worn Cobble)
Arenite (variable composition, primarily SiO2)
Sandstone (River Cobble)
Clastic sedimentary rock (primarily SiO2 with various lithic fragments)
Chalcedony (Agate/Carnelian precursor)
Chalcedony (Silicon Dioxide, SiO2)
Sandstone with Secondary Mineral Encrustation
Arenite with Silica/Calcite deposits (SiO2 or CaCO3)
Fossiliferous Limestone with Crinoid stems
Calcite-rich Biogenic Sedimentary Rock (CaCO3)
Chert (Nodule/Pebble)
Chert (Silicon Dioxide, SiO2)
Granite Gneiss with Garnet
Garnetiferous Gneiss
Clear Quartz
Quartz (Silicon Dioxide, SiO2)
Conglomerate
Clastic sedimentary rock (Conglomerate)