Petrified Wood and Mixed Rocks
Silicified Wood (SiO2)
Category
Browse organic materia (not a rock or mineral) specimens identified by the Rock Identifier community.
Petrified Wood and Mixed Rocks
Silicified Wood (SiO2)
Jasper
Silicon Dioxide (SiO2) with impurities
Chert (often called Jasper or River Rock)
Chert (SiO2)
Shungite
Non-crystalline carbon (high-carbon metamorphic rock)
Red Coral (Sponge Coral / Apple Coral)
Corallium rubrum (calcium carbonate / organic gem)
Chert (Chert / Flint)
Silicon dioxide (SiO2) - Microcrystalline quartz
Chert (Nodule)
Silicon Dioxide (SiO2)
Shungite
Non-crystalline carbon (allotrope of carbon)
Limestone (Weathered)
Calcium Carbonate (CaCO3)
Chert (Flint Pebbles)
Chert (SiO2)
Petrified Wood
Silicified Wood (SiO2)
Chert (Jasper/Quartzite Pebble)
Silicon Dioxide (SiO2)
Chert (Flint/Jasper variety)
Microcrystalline Quartz (SiO2)
Chert (often called Jasper or Flint)
Microcrystalline Quartz (SiO2)
Chert (and/or River Pebble)
Microcrystalline silica (SiO2)
Fossiliferous Limestone
Biogenic Limestone (Calcium Carbonate, CaCO3)
Chert (Nodular Chert)
Silicon Dioxide (SiO2)
Limestone Boulder
Sedimentary Rock (Calcium Carbonate, CaCO3)
Chert (Jasper/Agate Peat)
Microcrystalline Quartz (SiO2)
Pyrite
Iron Sulfide (FeS2)
Chert (Flint variety)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (with Quartz veins)
Microcrystalline Quartz (SiO2)
Red Chert (Jasper)
Silicon Dioxide (SiO2)
Nacre (Mother of Pearl)
Nacre (Biogenic Aragonite/Calcite composite, CaCO3)
Travertine / Tufa
Calcium Carbonate (CaCO3)
Limestone (Fossiliferous)
Sedimentary Carbonate Rock (CaCO3)
Chert (Jasper/Flint variety)
Microcrystalline Quartz (SiO2)
Chert (Jasper/Ironstone variety)
Silicon Dioxide (SiO2) with iron oxide inclusions
Shale or Argillite
Shale (sedimentary) / Argillite (metamorphic)
Polished green moss agate cabochon
Moss agate: microcrystalline quartz (SiO₂) with included chlorite/actinolite or iron-manganese minerals
Chert
Microcrystalline Quartz (SiO2)
Chert (specifically Flint or Jasper variant)
Cryptocrystalline Quartz (SiO2)
Chert (Jasper/Flint variety)
Microcrystalline quartz (SiO2)
Chert (Nodular)
Microcrystalline Silica (SiO2)
Chert (Flint)
Chert (Silicon Dioxide, SiO2)
Amber
Succinates (Fossilized Resin)
Chert (Jasper variation)
Silicon Dioxide (SiO2)
Amber
Succinite (Fossilized Tree Resin)
Coal
Bituminous coal (Complex organic sedimentary rock)
Bituminous Coal
Organic-rich sedimentary rock (Complex hydrocarbons)
Likely chert or flint
Microcrystalline quartz (SiO₂), commonly called chert; exact identification requires testing
Fossil Shark Tooth
Otodus sp. or Carcharocles sp. (likely fossilized Chondrichthyes)