Fossiliferous Limestone
Bioclastic Limestone
Category
Browse organic material specimens identified by the Rock Identifier community.
Fossiliferous Limestone
Bioclastic Limestone
Agatized Fossil (Druzy Agate)
Silicon Dioxide (SiO2) replacing organic matter
Petrified Wood
Silicified wood (Quartz/Chalcedony replacement of Cellulose)
Chert (often called Flint when dark)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (Flint)
Silicon Dioxide (SiO2)
Chert (Flint Pebble)
Cryptocrystalline Quartz (SiO2)
Chert (Jasper/Flint variety)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (Basanite / Jasperoid)
Microcrystalline Quartz (SiO2)
Calligraphy Stone
Mariam Jasper (Fossiliferous Limestone with Hematite and Iron)
Petrified Wood
Silicified wood (Quartz/Chalcedony - SiO2)
Chert (Flint)
Microcrystalline Quartz (SiO2)
Chert (Flint)
Chert (Silicon Dioxide, SiO2)
Chert
Microcrystalline Quartz (SiO2)
Carved red coral bead (likely coral or coral-colored resin)
Corallium spp. (precious coral; calcium carbonate, CaCO₃)
Banded Chert
Silicon Dioxide (SiO2)
Crushed Limestone
Sedimentary Calcite/Dolomite Rock (CaCO3)
Petrified Wood
Silicified Wood (SiO2)
Chert
Microcrystalline Quartz (SiO2)
Polished amber-like chalcedony/jasper
Microcrystalline quartz (SiO₂), likely iron-stained chalcedony or jasper; amber cannot be confirmed visually
Petrified Wood
Silicified Wood (primarily SiO2)
Coquina or Fossiliferous Limestone
Fossiliferous Calcarenite (CaCO3)
Chert
Cryptocrystalline Quartz (SiO2)
Chert (Flint)
Silicon Dioxide (SiO2)
Petrified Wood
Silicified Wood (SiO2 permineralization)
Chert (Flint)
Chert (SiO2)
Chert (Chalcedony/Flint)
Silicon Dioxide (SiO2)
Flint
Chert (Silicon dioxide, SiO2)
Limestone (Fossiliferous)
Calcium Carbonate (CaCO3)
Chert (variations include Flint)
Microcrystalline or cryptocrystalline Quartz (SiO2)
Amber
Succinite (organic gemstone, approx. C10H16O)
Limestone
Calcium Carbonate (CaCO3)
Petrified Wood
Silicified Wood (SiO2)
Petrified Wood Fragment
Silicified Wood (SiO2)
Petrified wood
Silicified wood, commonly quartz (SiO₂) replacing woody tissue
Chert (likely brown flint)
Microcrystalline quartz, SiO₂ (chalcedonic quartz aggregate)
Chert (Flint Nodules)
Silicon Dioxide (SiO2)
Chert (Flint)
Silicon Dioxide (SiO2)
Petrified Wood
Silicified Wood (primarily SiO2)
Petrified Wood
Silicified Wood (SiO2)
Mammoth or Mastodon Tooth Fragment
Mammuthus / Mammut molar fragment
Chert (often called Flint in this context)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Coprolite
Fossilized Feces