Dendritic Opal (Common Opal)
Amorphous Hydrated Silica (SiO2·nH2O) with Manganese or Iron Oxide inclusions
Category
Browse sedimentary (fossilized organic remain) specimens identified by the Rock Identifier community.
Dendritic Opal (Common Opal)
Amorphous Hydrated Silica (SiO2·nH2O) with Manganese or Iron Oxide inclusions
Freshwater Pearl
Aragonite / Biogenic Calcium Carbonate (CaCO3)
Graphite
Graphite (Native Carbon, C)
Petrified Wood
Silicified Wood (SiO2)
Petrified Wood
Silicified Wood (SiO2)
Jasper
Jasper (Silica-rich microcrystalline Quartz, SiO2 with Fe2O3 impurities)
Petrified Wood
Silicified wood (Quartz, SiO2)
Red Jasper
Jasper (Silicon Dioxide with Iron inclusions - SiO2)
Anthracite Coal
Anthracite
Jasper (Mookaite variety likely)
Silicon Dioxide (SiO2) with iron oxide inclusions
Septarian Nodule (Dragon Stone)
Septarian Concretion (CaCO3 with Siderite and Calcite)
Septarian Nodule or Mud Crack Fossil
Septarian Nodule (Concretion)
Petrified Wood
Silicified Wood (SiO2)
Septarian Nodule (Dragon Stone)
Septarian Geode (CaCO3 + Mg + Fe)
Petrified Wood
Silicified Wood (SiO2)
Horse Chestnut (Buckeye seed)
Aesculus hippocastanum seed
Black Pearl (Tahitian Pearl)
Aragonite / Calcite (CaCO3) with Conchiolin
Asphalt (Bituminous pavement)
Bituminous concrete / Asphalt
Jasper with Quartz Vein
Silicon Dioxide (SiO2) - Microcrystalline Quartz
Yellow Jasper (Iron-stained Chert)
Silicon Dioxide (SiO2) with iron oxide (Limonite/Goethite) inclusions
Chert (Grey-Green Var.)
Silicon Dioxide (SiO2)
Shale or Mudstone (Based on appearance)
Shale (fine-grained, laminated fissile sedimentary rock) / Mudstone (fine-grained, non-fissile sedimentary rock)
Orange Calcite
Calcium Carbonate (CaCO3)
Ironstone Concretion / Limonite Node
Ferruginous Sedimentary Rock (composed primarily of Limonite FeO(OH)·nH2O and Goethite)
Jasper (Petrified Wood variant)
Silicon Dioxide (SiO2) - Microcrystalline Quartz
Petrified Wood
Silicified Wood (SiO2)
Petrified Wood
Silicified wood (Quartz/Chalcedony - SiO2)
Petrified Wood
Silicified Wood (SiO2)
Chert (Nodular)
Chert (SiO2 - Microcrystalline Quartz)
Jasper (likely Brown or Brecciated)
Jasper (Silicon Dioxide, SiO2)
Petrified Wood
Silicified Wood (primarily SiO2)
Septarian Nodule
Septarian Concretion (CaCO3 with Siderite/Calcite/Aragonite)
Jasper
Jasper (Silicon Dioxide, SiO2)
Shale
Shale
Septarian Nodule
Septarian Concretion
Chert (Arrowhead or Projectile Point)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (Chert Nodule)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Pearl
Calcium carbonate (CaCO3) as Aragonite or Calcite
Pearl
Calcium Carbonate (CaCO3) with Conchiolin
Petrified Wood
Silicified Wood (primarily Quartz / Chalcedony: SiO2)
Red Jasper
Silicon dioxide (SiO2) with Iron Oxide (Fe2O3) inclusions
Travertine (Tufa)
Calcium Carbonate (CaCO3)