Marble
Recrystallized Calcite (CaCO3) Rock
Category
Browse sedimentary (fossiliferous) specimens identified by the Rock Identifier community.
Marble
Recrystallized Calcite (CaCO3) Rock
Marble
Recrystallized Calcite (CaCO3) or Dolomite (CaMg(CO3)2)
Bumblebee Jasper
Calcite with Arsenic and Manganese oxides (technically a volcanic rock)
Chert (often called Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Pyrite (Fool's Gold)
Iron Sulfide (FeS2)
Calcite (Iceland Spar)
Calcite (Calcium Carbonate, CaCO3)
Pyrite (Fool's Gold)
Iron Disulfide (FeS2)
Chalcedony (Common Opal variant or Quartz)
Silicon Dioxide (SiO2)
Petrified Wood
Silicified wood (Quartz/Chalcedony replacement of organic matter)
Chert (Tan/Yellow variety)
Microcrystalline or cryptocrystalline Quartz (SiO2)
Red Sandstone
Arenite (with Iron Oxide / Hematite), Formula: SiO2 (Quartz) + Fe2O3 (Hematite coating)
Petrified Wood
Silicified Wood (SiO2)
Crinoid Fossil in Limestone
Class Crinoidea in Carbonate Matrix (CaCO3)
Red Sandstone
Clastic Terrigenous Sedimentary Rock (typically Hematitic Quartz Arenite or Arkose)
Chert (and Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Sandstone
Arenite (primarily SiO2)
Chert (White Chert/Flint)
Chert (Microcrystalline or Cryptocrystalline Quartz, SiO2)
Petrified Wood
Silicified Wood (primarily SiO2)
Siltstone
Siltstone (primarily SiO2 with Al2O3)
Chert (Commonly known as Flint or Jasper when pigmented)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Limonite (Ironstone Concretion)
Limonite (Hydrous ferric oxide mixture, FeO(OH)·nH2O)
Chert (Jasper)
Cryptocrystalline Quartz (SiO2)
Chert (Red Jasper)
Microcrystalline Quartz (SiO2)
Chert (and Limestone)
Silicon Dioxide (SiO2)
Chert (often called Flint for dark variants)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Red Sandstone
Arenite (Ferruginous Sandstone)
Chert (Pink/Red variety)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Siltstone
Siltstone
Chert (White-Tan variety)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Limonite and Goethite encrusted Chert/Ironstone
Hydrated Iron Oxide (FeO(OH)·nH2O) with cryptocrystalline Silica (SiO2)
Jasper (likely Brown or Brecciated)
Jasper (Silicon Dioxide, SiO2)
Sandstone
Arenite (primarily SiO2)
Geode with Quartz and Chalcedony
Silicon Dioxide (SiO2)
Sandstone (Ferruginous)
Arenite with Iron Oxide cement (SiO2 + Fe2O3)
Limestone
Calcium Carbonate (CaCO3)
Limonitic Sandstone with Inclusion
Limonitic Quartz Sandstone (primarily SiO2 with FeO(OH)·nH2O)
Sandstone (Yellow/Tan)
Clastic sedimentary rock (primarily SiO2 with iron oxide staining)
Chert
Chert (Microcrystalline Silica, SiO2)
Shale or Siltstone
Sedimentary Clastic Rock (Variable mineral composition including quartz and clay minerals)
Limestone
Calcium Carbonate (primarily CaCO3 as Calcite or Aragonite)
Sandstone (likely Fossilized Wood or Concrete Simulacrum)
Arenite / Silicified Wood / Anthropogenic Concrete
Chert (Brecciated Chert)
Silicon Dioxide (SiO2)