Chert (often called Flint or River Stone)
Microcrystalline alpha-quartz (SiO2)
Category
Browse organic material (likely a fruit or berry) specimens identified by the Rock Identifier community.
Chert (often called Flint or River Stone)
Microcrystalline alpha-quartz (SiO2)
Chert (Flint)
Chert (SiO2)
Chert (Green variety)
Silicon Dioxide (SiO2)
Chert (Flint variety)
Chert (Cryptocrystalline Quartz, SiO2)
Sandstone (Calcareous Sandstone)
Calcareous Sandstone (primarily SiO2 with CaCO3 cement)
Chert (often called Flint)
Silicon Dioxide (SiO2)
Petrified Wood
Silicified wood (Quartz/Chalcedony replacement of Cellulose)
Chert (Arrowhead Preform)
Silicon Dioxide (SiO2) - Microcrystalline Quartz
Yellow Jasper
Silicon Dioxide (SiO2) with iron inclusions
Chert / Flint
Silicon Dioxide (SiO2)
Possible weathered quartz-rich rock or iron-stained mineral fragment
Indeterminate; possibly quartz (SiO₂) with iron-oxide inclusions
Rhyolitic Tuff
Rhyolitic Tuff / Pyroclastic rock
Travertine
Travertine (a terrestrial form of Limestone, CaCO3)
Chert
Microcrystalline Quartz (SiO2)
Chert (Jasper/Chalcedony)
Microcrystalline Quartz (SiO2)
Chert (with Quartz Druzy)
Microcrystalline Silica (SiO2)
Gravel / Limestone Fragment
Calcium Carbonate (CaCO3) / Fine-grained Sedimentary Rock
Chert (Yellow Jasper)
Microcrystalline Quartz (SiO2)
Chert (Jasper)
Microcrystalline Quartz (SiO2) with Iron Oxide inclusions
Botiroidal Chalcedony or Silicified Fossil Coral
Silicon Dioxide (SiO2) - Chalcedony / Scleractinia (if fossilized)
Petrified Wood
Silicified Wood (primarily SiO2)
Chert (Jasper variety)
Silicon Dioxide (SiO2)
Chert (variations include Flint or Jasper)
Aphanitic Silica (SiO2)
Chert (Jasper)
Silicon Dioxide (SiO2)
Chert (Chert / Flint)
Silicon Dioxide (SiO2)
Chert (Flint)
Silicon Dioxide (SiO2) - Microcrystalline Quartz
Lava Rock with Fabric Impression
Scoria or Basalt with anthropogenic impressions
Chert Pebble
Microcrystalline Quartz (SiO2)
Amber
Succinite (C10H16O)
Metal Chain Belt with Square Plates
Not applicable (man-made)
Chert (Flint)
Silicon Dioxide (SiO2)
Limestone
Sedimentary rock composed mainly of calcite (CaCO3)
Chert / Flint
Silicon Dioxide (SiO2) - Microcrystalline Quartz
Fossiliferous Limestone
Calcium Carbonate (CaCO3) with fossil inclusions
Quartzite
Quartzite (primarily SiO2)
Amber
Succinite (specifically for Baltic amber); approximate formula C10H16O
Petrified Wood
Silicified Wood (SiO2)
Milky Quartz with Iron Staining
Silicon Dioxide (SiO2)
Chalcedony (Agate Pebble)
Silicon Dioxide (SiO2)
Travertine (Tufa)
Chemical Limestone (CaCO3)
Polished granite
Granite; chiefly quartz, feldspar, and mica/amphibole
Chert (Flint Nodules)
Chert (Microcrystalline Quartz, SiO2)