Polygenetic Breccia
Clastic Breccia (containing lithic fragments in a fine-grained matrix)
Category
Browse sedimentary rock (specifically a clastic sedimentary rock formed into a cobble) specimens identified by the Rock Identifier community.
Polygenetic Breccia
Clastic Breccia (containing lithic fragments in a fine-grained matrix)
Milky Quartz in Conglomerate Matrix
Silicon Dioxide (SiO2) within Clastic Sedimentary Rock
Chert (specifically a weathered Chert nodule or fragment)
Chert; Microcrystalline or Cryptocrystalline Quartz (SiO2)
Ferruginous Breccia
Breccia with Iron-rich (Hematite/Goethite) Matrix
Chert (specifically Flint or Common Chert node)
Silicon Dioxide (SiO2)
Red Sandstone
Arenite (high iron oxide content)
Shale (with minor calcite veining)
Clastic sedimentary rock (primarily clay minerals and quartz)
Sandstone
Sandstone (arenite is a more specific geological term for a clean sandstone, while wacke refers to a dirty sandstone with significant matrix)
Chert (specifically Flint or Jasper variant)
Chert (Siliceous rock composed of microcrystalline Quartz, SiO2)
Sandstone (Red/Brown Variety)
Arenite (composed primarily of SiO2 with Fe2O3 iron oxide inclusions)
Gneiss (specifically Micaceous Gneiss)
Gneiss (High-grade Regional Metamorphic Rock)
Chert (specifically Flint or Jasper variant)
Cryptocrystalline Quartz (SiO2)
Siltstone with Quartz Vein
Siltstone (primarily SiO2, Al2O3, Fe2O3)
Sandstone Beach Pebble
Clastic Sandstone (SiO2 - Quartz-dominant)
Porphyry
Porphyritic Rock
Fossiliferous Shale (with Vertebrate Bones)
Laminated Mudstone containing Fossilized Bone (Apatite)
Puddingstone
Conglomerate (Indurated)
Sandstone (likely Quartzose Sandstone)
Arenite
Gneiss (specifically Pink Gneiss)
Gneiss (high-grade regional metamorphic rock)
Fossiliferous Limestone (Coquina / Shell Limestone)
Biogenic Limestone (Calcium Carbonate, CaCO3)
Chert (specifically Pink Chert or Jasperized Chert)
Silicon Dioxide (SiO2) - Cryptocrystalline Quartz
Red Sandstone
Arenite (Fe2O3 rich)
Ferruginous Sandstone (Gozzan)
Iron-rich clastic sedimentary rock with Limonite/Goethite
Chert (specifically Tan/Yellow Chert)
Chert (Microcrystalline or Cryptocrystalline Silica, SiO2)
Banded Sandstone (Quartzite-rich)
Clastic Sedimentary Rock (SiO2 with Iron Oxide impurities)
Ocherous Sandstone (Ferruginous Sandstone)
Ferruginous Arenite (SiO2 with Fe2O3)
Crazy Lace Agate
Chalcedony (Silicon Dioxide, SiO2)
Liesegang Ring Siltstone
Siltstone with iron oxide Liesegang bands
Basalt
Basalt
Coquina
Biogenic Limestone (Calcium Carbonate, CaCO3)
Quartzite Cobble
Quartzite (primarily SiO2)
Quartz Vein in Host Rock (clastic sediment)
Silicon Dioxide (SiO2) in matrix
Sandstone (with Iron Oxide)
Arenite with Limonite/Hematite staining
Gneiss (Stream-worn Cobble)
Gneiss (Metamorphic rock composed primarily of Quartz, Feldspar, and Mica)
Sandstone with trace fossil
Sandstone, possibly with Skolithos or similar trace fossil
Red Sandstone
Arenite (predominantly Quartz with Hematite cementation)
Red Sandstone
Arenite (Fe2O3-rich)
Sandstone (Red Sandstone / River Stone)
Arenite (composed primarily of Quartz, SiO2, with Iron Oxide cementation)
Graywacke
Graywacke (immature sandstone)
Red Sandstone
Arenite (with Iron Oxide / Hematite cementation)
Red Sandstone
Arenite (primarily Quartz with Hematite cement)
Basalt (River Rock Cobble)
Extrusive mafic igneous rock