Fossilized Sea Urchin (Echinoid)
Echinoidea (Class); commonly Clypeasteroida for sand dollar types
Category
Browse anthropogenic sedimentary (man made) specimens identified by the Rock Identifier community.
Fossilized Sea Urchin (Echinoid)
Echinoidea (Class); commonly Clypeasteroida for sand dollar types
Limonite (often after Hematite or Goethite)
Limonite (FeO(OH)·nH2O)
Druzy Quartz on Host Rock
Silicon Dioxide (SiO2)
Coquina / Shelly Limestone
Bioclastic Limestone (composed of CaCO3)
Black Opal
Hydrated Silica (SiO2·nH2O)
Limonite (Iron Ore)
FeO(OH)·nH2O (Hydrated Iron Oxide)
Petrified Wood
Silicified Wood (primarily SiO2)
Jasper and Chert Conglomerate
Ferruginous Microcrystalline Quartz (SiO2)
Chert (Flint)
Microcrystalline Quartz (SiO2)
Jasper
Jasper (Silicon Dioxide, SiO2)
Banded Chert
Microcrystalline Quartz (SiO2)
Gneiss (with Quartz and Mica)
Gneiss
Rough Agate/Chert Nodules
Cryptocrystalline Quartz (SiO2)
Leopardskin Jasper
Jasper (a variety of microcrystalline Quartz)
Chert (Jasper)
Silicon Dioxide (SiO2)
Fossilized Horn Coral
Order Rugosa (Rugose Coral)
Agate (River Pea)
Microcrystalline Chalcedony (SiO2)
Chalcedony (Agate)
Silicon Dioxide (SiO2)
Black Opal
Hydrated silica (SiO2·nH2O)
Wishing Stone (Quartz-veined Siltstone or Graywacke)
Hydrothermal Quartz vein in matrix of SiO2 (Quartz) and Al2O3 (Clay minerals)
River Stone / Pebble
Clastic Sediment (composed largely of Quartz, Feldspar, and various rock fragments)
Magnetite
Magnetite (Fe3O4)
Carnelian
Carnelian Agate (Silica: SiO2)
Chert (Flint)
Silicon Dioxide (SiO2)
Fossiliferous Limestone
Calcium Carbonate (CaCO3) with Biogenic Inclusions
Chert (Chert Nodule)
Silicon Dioxide (SiO₂)
Zebra Rock (Zebra Stone / Ribbon Stone)
Siltstone with Ferruginous Banding (Primarily Quartz, Kaolinite, and Hematite)
Fossiliferous Limestone (with Coralline Inclusions)
Calcium Carbonate (CaCO3)
Chert / Flint
Silicon Dioxide (SiO2)
Fossiliferous Limestone (with Crinoids/Coral)
Fossiliferous Limestone (CaCO3)
Jasper
Silicon dioxide (SiO2) with iron impurities
Red Jasper
Jasper (SiO2 with Fe2O3 inclusions)
Red Jasper
Silicon Dioxide with Hematite inclusions (SiO2 + Fe2O3)
Chert (Flint)
Microcrystalline Quartz (SiO2)
Blue Howlite (Dyed)
Calcium Borosilicate Hydroxide (Ca2B5SiO9(OH)5)
Jasper (Iron-stained Quartz)
Silicon dioxide (SiO2) with iron oxide inclusions
Fluorite (Green Fluorite)
Calcium Fluoride (CaF2)
Calcite
Calcite (CaCO3)
Jasper with Dendritic Inclusions
Silicon Dioxide (SiO2) - Microcrystalline Quartz
Chert (Jasper/Common Opal mix)
Microcrystalline Quartz (SiO2)
Picture Jasper
Silicon Dioxide (SiO2) with iron oxide inclusions
Yellow Jasper
Jasper (Silicon Dioxide, SiO2)