Anthracite Coal
Anthracite
Category
Browse organic (paper and cellulose) specimens identified by the Rock Identifier community.
Anthracite Coal
Anthracite
Anthracite Coal
Anthracite
Chert (Jasper)
Silicon Dioxide (SiO2)
Limestone (River Pebble)
Calcium Carbonate (CaCO3)
Black Jasper (Etched)
Silicon Dioxide (SiO2) with impurities
Chert (Flint)
Microcrystalline or cryptocrystalline Quartz (SiO2)
Unidentified Dark Mineral or Rock
Indeterminate (Likely Silicon Dioxide or Carbon-based)
Jasper
Silicon Dioxide (SiO2)
Mammoth Molar Fossil
Mammuthus primigenius (Tooth fragment)
Fossil Shark Tooth
Chondrichthyes (Class)
Fossilized Brachiopod
Brachiopoda (Phylum)
Fossil Shark Tooth
Lamniformes (order) - likely Cretalamna or Carcharias species
Septarian Nodule
Calcite-bearing Septarian Concretion
Chert (Flint)
Silicon dioxide (SiO2)
Chert (Jasper variety)
Microcrystalline Quartz (SiO2)
Chert (Nodule)
Cryptocrystalline Quartz (SiO2)
Banded Chert
Silicon Dioxide (SiO2)
Limestone
Calcium Carbonate (CaCO3)
Chert (often called Flint)
Microcrystalline quartz (SiO2)
Chert (Flint)
Silicon Dioxide (SiO2)
Gray River Pebble (likely Limestone or Siltstone)
Sedimentary Rock (Calcium Carbonate or Siliciclastic)
Chert (Flint)
Silicon dioxide (SiO2)
Chert (Flint Nodules)
Cryptocrystalline Quartz (SiO2)
Bivalve Fossil in Sedimentary Matrix
Fossiliferous Mudstone (Class: Bivalvia)
Banded Chert (River Pebble)
Microcrystalline Quartz (SiO2)
Chert (with nodule)
Microcrystalline Quartz (SiO2)
Chert (Mudstone)
Microcrystalline Quartz (SiO2)
Chert / Flint
Chert (Microcrystalline Quartz, SiO2)
Asphalt (Bituminous pavement)
Bituminous concrete / Asphalt
Chert / Chalcedony
Microcrystalline Quartz (SiO2)
Chert (often called Flint when dark)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert
Microcrystalline Quartz (SiO2)
Petrified Wood
Silicified Wood (SiO2)
Chert Pebble
Microcrystalline Quartz (SiO2)
Fossilized Shark Tooth (Partial) or Coprolite
Elasmobranchii (fossil) or Coprolite (trace fossil)
Banded Limestone
Calcareous sedimentary rock (CaCO3)
Petrified Wood
Silicified Wood (mainly Quartz/Chalcedony, SiO2)
Fossil Shark Tooth (Sand Tiger Shark type)
Carcharias sp. (likely Odontaspis)
Chert (Flint)
Silicon Dioxide (SiO2)
Chert (Jasper variation)
Silicon Dioxide (SiO2)
Fossilized Shark Tooth (Anterior/Lateral)
Otodus megalodon or Carcharodon carcharias (fossilized)
Chert (Jasper)
Silicon Dioxide (SiO2)