Limestone
Sedimentary rock composed mainly of calcite (CaCO3)
Category
Browse organic mineraloid specimens identified by the Rock Identifier community.
Limestone
Sedimentary rock composed mainly of calcite (CaCO3)
Petrified Wood
Silicified Wood (Per mineral content: SiO2, Quartz/Chalcedony)
Chert
Microcrystalline Quartz (SiO2)
Chert
Opaline or Microcrystalline Jasper/Chert (SiO2)
Chert Nodule
Chert (Microcrystalline Silicon Dioxide, SiO2)
Banded Chert
Silicon dioxide (SiO2) with impurities
Chert (Field Stone)
Silicon Dioxide (SiO2)
Chert (Yellow Jasper variant)
Microcrystalline Quartz (SiO2)
Chert (Jasper)
Silicon Dioxide (SiO2)
Chert (Jasper/Basalt River Pebble)
Silicon Dioxide (SiO2) or Microcrystalline Quartz
Chert (Flint)
Microcrystalline Quartz (SiO2)
Petrified Wood
Silicified Wood (SiO2)
Chert
Microcrystalline Quartz (SiO2)
Anthracite Coal
Anthracite
Fossilized Coral in Chert
Anthozoa (Class) fossil in Cryptocrystalline Quartz (SiO2)
Fossilized Shark Tooth
Eocene Lamniformes (Mackerel Shark clade)
Banded Chert (Flint)
Silicon Dioxide (SiO2)
Fossilized Bone
Vertebrate Fossil Fragment (Calcium Phosphate / Hydroxyapatite)
Petrified Wood
Silicified Wood (SiO2 permineralization)
Chert (Red/Pink variety)
Microcrystalline quartz (SiO2)
Chert (and Jasper)
Microcrystalline Quartz (SiO2)
Banded Chert (Jasper)
Silicon Dioxide (SiO2) with iron oxide inclusions
Chert Pebble
Microcrystalline Quartz (SiO2)
Fossiliferous Limestone
Biogenic Limestone (Calcium Carbonate, CaCO3)
Chert
Microcrystalline Silicon Dioxide (SiO2)
Chert (Iron-stained)
Microcrystalline silica (SiO2) with trace Iron oxide (Fe2O3)
Chert (Jasper)
Microcrystalline Quartz (SiO2) with Iron Oxide inclusions
Chert / Flint
Chert (Cryptocrystalline Quartz, SiO2)
Jasper
Silicon dioxide (SiO2)
Chert / Flint (with quartz or calcite inclusion)
Silicon dioxide (SiO2)
Coprolite
Coprolite (fossilized feces)
Chert (River Pebble)
Microcrystalline Quartz (SiO2)
Chert (Flint variety)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (Cherty Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (Nodular Chert)
Silicon Dioxide (SiO2)
Pyrite in Limestone
Iron Sulfide (FeS2) in Calcium Carbonate (CaCO3)
Pearl
Calcium Carbonate (mostly Aragonite), CaCO3 (with conchiolin)
Chert (Arrowhead variety)
Chert (SiO2)
Chert (Flint/Jasper variety)
Microcrystalline Quartz (SiO2)
Chert (Flint)
Microcrystalline Silica (SiO2)
Petrified Wood
Silicified wood (primarily SiO2)
Chert (with Limonite staining)
Microcrystalline Quartz (SiO2)