Ironstone Concretion
Goethite-rich Siltstone / Siderite (FeCO3)
Category
Browse organic (anthropogenic) specimens identified by the Rock Identifier community.
Ironstone Concretion
Goethite-rich Siltstone / Siderite (FeCO3)
Agatized Fossil or Chalcedony Nodule
Silicon Dioxide (SiO2) - Cryptocrystalline Quartz
Chert (Jasper transition)
Microcrystalline Quartz (SiO2)
Chert (varieties include Flint and Jasper)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (Jasper/Flint variety)
Microcrystalline quartz (SiO2)
Chert (Flint)
Chert (̑SiO2)
Chert (Jasper)
Microcrystalline Quartz (SiO2)
Chert (Yellow Jasper/Flint)
Silicon Dioxide (SiO2) - Microcrystalline Quartz
Pearl
Aragonite / Calcium Carbonate (CaCO3)
Chert Pebble
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Petrified Wood
Silicified Wood (primarily Chalcedony or Quartz, SiO2)
Yellow Chert (Jasper)
Silicon Dioxide (SiO2)
Geode (Unopened)
SiO2 (Quartz-filled Sedimentary Nodule)
Pyrite Geode (Sparkling Druzy)
Iron Sulfide (FeS2) in Sedimentary Nodule
Chert (containing Iron Oxide spots)
Microcrystalline Quartz (SiO2)
Chert (varieties include Flint and Mudstone)
Microcrystalline Silica (SiO2)
Chert Pebble
Chert (Microcrystalline Quartz, SiO2)
Chert (and Quartzite)
Microcrystalline silica (SiO2)
Chert (Pebble)
Chert (Microcrystalline Quartz, SiO2)
Chert / Flint
Silicon Dioxide (SiO2)
Petrified Wood
Silicified Wood (primarily SiO2)
Chert (Flint)
Silicon Dioxide (SiO2) - Microcrystalline Quartz
Chert (Pebble)
Chert (Microcrystalline Quartz, SiO2)
Chert (Flint)
Microcrystalline Quartz (SiO2)
Fossilized Shark Tooth (Otodus)
Otodus sp. (calcium phosphate/hydroxylellite)
Chert (Flint)
Silicon Dioxide (SiO2)
Chert (specifically Flint or Novaculite variant)
Chert (Microcrystalline Quartz, SiO2)
Chert (Black Flint)
Silicon Dioxide (SiO2)
Geode (unopened)
Chert / Chalcedony Geode (SiO2)
Petrified Wood
Silicified Wood (primarily SiO2)
Chert
Chert (Microcrystalline Quartz, SiO2)
Chert (Flint)
Cryptocrystalline Quartz (SiO2)
Chert (Pebble)
Microcrystalline silica (SiO2)
Pyrite
Iron Disulfide (FeS2)
Chert (and Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Petrified Wood (Calamites Fossil)
Calamites sp. (Silicified/Permineralized Plant Fossil)
Chert
Sedimentary Cryptocrystalline Quartz (SiO2)
Petrified Wood
Silicified Wood (SiO2)
Chert (Jasper/Flint variety)
Microcrystalline Quartz (SiO2)
Petrified Wood
Silicified Wood (SiO2)
Chert (River Pebble)
Microcrystalline Quartz (SiO2)
Fossilized Coral (Favosites)
Favosites (extinct genus of tabulate coral)