Chert (Nodular)
Chert (SiO2 - Microcrystalline Quartz)
Category
Browse organic (pseudo geological) specimens identified by the Rock Identifier community.
Chert (Nodular)
Chert (SiO2 - Microcrystalline Quartz)
Chert Pebble with Quartz Veins
Microcrystalline Quartz (SiO2)
Chert (specifically Tan/Brown Chert)
Chert (SiO2)
Petrified Wood
Silicified Wood (SiO2)
Chalk
Calcium Carbonate (CaCO3)
Coal (most likely Bituminous or Anthracite)
Coal (organic sedimentary rock)
Petrified Wood
Silicified Wood (SiO2)
Limestone (Concretionary or Tufa)
Calcium Carbonate (CaCO3)
Shale
Shale (fine-grained clastic sedimentary rock)
Petrified Wood
Silicified Wood (SiO2)
Petrified Wood
Silicified Wood (SiO2)
Petrified Wood
Silicified Wood (SiO2)
Moss Agate
Cryptocrystalline Quartz (SiO2 with Manganese or Iron Oxide inclusions)
Chert (Septarian or Nodular variety)
Microcrystalline Quartz (SiO2)
Moqui Marble (Shaman Stone)
Iron Oxide Concretion (composed primarily of Quartz sand with Hematite/Goethite shell)
Petrified Wood
Silicified Wood (SiO2 - primarily Quartz/Chalcedony/Opal)
Red Jasper
Silicon dioxide (SiO2) with Iron Oxide (Fe2O3) inclusions
Limestone
Calcium Carbonate (CaCO3)
Yellow Chert
Sedimentary cryptocrystalline quartz (SiO2)
Jasper
Jasper (Silicon Dioxide, SiO2)
Green Jasper (with Quartz veining)
Jasper (Silica-rich microcrystalline variety of Quartz), formula: SiO2
Banded Chert
Microcrystalline Quartz (SiO2)
Fossiliferous Brachiopod in Shale
Brachiopoda (Phylum) preserved in Carbonaceous Shale
Ironstone Concretion (Iron-rich Mudstone)
Siderite / Geothite concretion (FeCO3 / FeO(OH))
Amber
Succinite (Carbon-based organic compound; approximate formula C10H16O)
Chert (Jasper variation)
Silicon Dioxide (SiO2) - Microcrystalline Quartz
Petrified Wood
Silicified Wood (primarily Quartz / Chalcedony: SiO2)
Limestone (Weathered)
Calcium Carbonate (CaCO3)
Quartz Geode in Chert/Limestone Matrix
Silicon Dioxide (SiO2) within Sedimentary Host Rock
Chert (River Pebble)
Microcrystalline Quartz (SiO2)
Ironstone Concretion
Siderite or Goethite Concretion
Chert (and Jasper variety)
Microcrystalline Quartz (SiO2)
Travertine
Calcareous Tufa (CaCO3)
Petrified Wood
Silicified wood (Quartz/Chalcedony - SiO2)
Travertine (Tufa)
Calcium Carbonate (CaCO3)
Petrified Wood
Silicified Wood (primarily SiO2 - Silicon Dioxide / Chalcedony)
Septarian Nodule (Dragon Stone)
Septarian Nodule (Calcium Carbonate/Aragonite/Calcite Concretion)
Petrified Wood
Silicified Wood (primarily SiO2)
Jasper
Agate/Jasper (Microcrystalline Quartz, SiO2)
Chert (Chert Nodule)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (Iron-stained River Cobble)
Microcrystalline Quartz (SiO2)
Graphite
Graphite (C)