Crushed Limestone
Calcite-rich Sedimentary Rock (CaCO3)
Category
Browse anthropogenic sedimentary style organic solid specimens identified by the Rock Identifier community.
Crushed Limestone
Calcite-rich Sedimentary Rock (CaCO3)
Anthracite Coal
Anthracite (Carbon-based organic sedimentary rock transitioned to metamorphic)
Shale
Fissile Clay-dominant Mudrock (SiO2, Al2O3, K2O, Na2O, CaO, MgO)
Banded Chert (with Quartz Vein)
Microcrystalline Silica (SiO2)
Limestone with Quartz/Calcite Veins
Sedimentary Limestone (CaCO3 with SiO2 or CaCO3 intrusions)
Petrified Wood
Silicified Wood (primarily SiO2)
Coral Fossil (Petrified Coral)
Scleractinia (Order) - Calcified Fossil Skeleton (CaCO3)
Chert (Chert Nodule)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Travertine (often colloquially called Tufa)
Chemical Sedimentary Calcium Carbonate (CaCO3)
Massive Cryptocrystalline Quartz (Chert/Chalcedony Pebble)
Silicon Dioxide (SiO2)
Chert (specifically Iron-stained River Cobble)
Silicon Dioxide (SiO2)
Chert (Jasper variety)
Silicon Dioxide (SiO2)
Green Banded Chert (Agate/Jasper)
Silicon Dioxide (SiO2) with trace impurities of Chlorite or Glauconite
Coquina
Biogenic Limestone (Calcium Carbonate, CaCO3)
Glauconitic Sandstone
Glauconitic Quartz-Wacke / Sandstone (Fe(II),Fe(III),Al,Mg)2-3(Si,Al)4O10(OH)2
Moss Agate
Silicon Dioxide (SiO2) with inclusions of Manganese or Iron oxides
Amber
Succinite (fossilized resin)
Petrified Wood
Silicified Wood (SiO2)
Chert (Brown variety / Common Jasper)
Microcrystalline Quartz (SiO2)
Chert (variously identified as Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Septarian Nodule (Thunder Egg)
Septarian Concretion (CaCO3 + CaMg(CO3)2 + SiO2)
Petoskey Stone
Hexagonaria percarinata (Fossilized Rugose Coral)
Chert (Iron-stained)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (Jasper/Flint variety)
Microcrystalline Quartz (SiO2)
Petrified Wood
Silicified Wood (primarily SiO2)
Ferruginous Sandstone (Ironstone)
Arenite with Iron-Oxide Cement (FeO(OH)·nH2O / Fe2O3)
Petrified Wood
Silicified Wood (primarily SiO₂ - Silicon Dioxide)
Graphite
Graphite (C)
Limestone
Calcium Carbonate (CaCO3)
Moss Agate
Silicon Dioxide with inclusions (SiO2 + impurities)
Petrified Wood
Silicified Wood (SiO2)
Fossilized Wood (with Coal and Limonite)
Petrified Wood (Silicified or Carbonized Flora)
Petrified Wood
Silicified Wood (primarily SiO2)
Chert (with Quartz vein)
Chert (Silicon Dioxide, SiO2)
Petrified Wood (Agatized/Silicified Wood)
Silicified Wood / Chalcedony (SiO2)
Jasper
Jasper (Silica-rich microcrystalline Quartz, SiO2 with Fe2O3 impurities)
Chert (Flint)
Chert (Cryptocrystalline variety of Quartz, SiO2)
Fossiliferous Brachiopod in Shale
Brachiopoda (Phylum) preserved in Carbonaceous Shale
Petrified Wood
Silicified Wood (primarily SiO₂ / Silicon Dioxide)
Chert (variant Flint/Jasper)
Microcrystalline Opaline Silica (SiO2)
Coquina
Biogenic Limestone (Calcium Carbonate - CaCO3)
Carnelian
Carnelian (a variety of Chalcedony, SiO2)