Sandstone (Quartzose Sandstone)
Arenite (SiO2 primarily)
Category
Browse sedimentary (base), then artificial specimens identified by the Rock Identifier community.
Sandstone (Quartzose Sandstone)
Arenite (SiO2 primarily)
Sandstone (Quartz Arenite)
Sandstone (SiO2 with possible mineral cements)
Sandstone (River Cobble)
Clastic sedimentary rock (primarily SiO2 with various lithic fragments)
Wishing Stone (Sandstone with Quartz Vein)
Arenite with Quartzite intrusion (SiO₂)
Sandstone (likely Greywacke or Lithic Sandstone)
Arenite / Wacke
Sandstone (Greywacke)
Clastic Sedimentary Rock (SiO2 with lithic fragments)
Siltstone
Siltstone (fined-grained clastic sedimentary rock)
Sandstone (with Iron Staining)
Clastic Sedimentary Rock (primarily SiO2 with FeO(OH) impurities)
Limestone (Fossiliferous)
Calcium Carbonate (CaCO3) - Bioclastic Limestone
Sandstone
Arenite (Secondary classification based on grain size)
Limestone
Calcium Carbonate (CaCO3)
Sandstone
Arenite (primarily SiO2)
Coquina
Bioclastic Limestone (composed primarily of CaCO3)
Conglomerate
Conglomerate (Rock composed predominantly of rounded clasts > 2mm)
Tufa
Calcium carbonate (CaCO3) - Porous Limestone
Shale
Fissile mudrock (composed of clay-sized particles and detrital grains)
Conglomerate
Conglomerate (clastic sedimentary rock)
Dalmatian Stone
Peralkaline rhyolite with arfvedsonite (formerly incorrectly called Dalmatian Jasper)
Common Brown Pebble
Weathered Rock Fragment
Limestone
Calcium Carbonate (CaCO3)
Sandstone (Ferruginous)
Arenite (complex silicate composition with iron oxides)
Limestone (with Calcite Veining)
Calcium Carbonate (CaCO3)
Greenschist
Greenschist (composed mainly of chlorite, epidote, actinolite, and albite)
Conglomerate
Clastic Sedimentary Rock (Conglomerate)
Granite
Granite
Dyed blue howlite (turquoise imitation), possibly dyed magnesite
Howlite: Ca₂B₅SiO₉(OH)₅; the vivid blue color is artificial dye. Exact identification is uncertain from the photograph alone.
Chalcedony (Botryoidal)
Silicon Dioxide (SiO2)
Quartz-veined Jasper
Microcrystalline quartz (SiO2) with quartz veins
Jasper River Stone
Silicon Dioxide with Iron Oxide impurities (SiO2 + Fe2O3)
Chert (Nodule)
Silicon dioxide (SiO2) - Cryptocrystalline Quartz
Chert Arrowhead
Microcrystalline Quartz (SiO2)
Siltstone with Fossil Cast
Sedimentary Rock (Siltstone / Fine-grained Sandstone)
Fossilized Coral (Favosites)
Favosites goldfussi
Fossil Shark Tooth
Elasmobranchii (Lamniformes order likely)
Gneiss (or Granite Gneiss)
Metamorphic rock rich in quartz, feldspar, and biotite/amphibole
Gneiss
Gneiss (Foliated Metamorphic Rock)
Gneiss
Gneiss (Metamorphic Rock)
Precious Opal
Hydrated Silica (SiO2·nH2O)
Jasper Pendant
Chalcedony (Quartz) - SiO2
Fossil Shark Tooth
Otodus sp. (Eocene shark fossil)
Limestone
Sedimentary Calcium Carbonate (CaCO3)
Orange Calcite
Calcium Carbonate (CaCO3)