Sandstone (Ferruginous)
Arenite with Hematite cement (SiO2 + Fe2O3)
Category
Browse sedimentary (biogenic) specimens identified by the Rock Identifier community.
Sandstone (Ferruginous)
Arenite with Hematite cement (SiO2 + Fe2O3)
Chert (Flint)
Silicon Dioxide (SiO2)
Coal
Bituminous or Anthracite coal (carbon-rich sedimentary rock)
Gastropod Fossil (Snail Steinkern)
Class Gastropoda fossil, composed of Calcium Carbonate (CaCO3)
Sandstone concretion (Ironstone-stained)
Arenite with Limonite/Hematite staining (Silica-based with Iron Oxides)
Banded Chert
Silicon Dioxide (SiO2)
Fossilized Gastropod in Limestone
Gastropoda (Class) in Calcium Carbonate (CaCO3)
Chert / Flint
Cryptocrystalline quartz (SiO2)
Sandstone (Water-worn Cobble)
Arenite (SiO2 based)
Sandstone (Quartzose)
Arenite (primarily SiO2)
Sandstone (likely Ferruginous)
Arenite (SiO2 based with Fe2O3/FeO(OH) cement)
Sandstone (Ferruginous)
Arenite (primarily SiO2 with Fe2O3 cementation)
Quartz (Druzy)
Silicon Dioxide (SiO2)
Sandstone with Quartz Vein
Arenite with SiO2 intrusion
Chert Nodules in Limestone
Microcrystalline Quartz (SiO2) within Calcium Carbonate (CaCO3)
Shale
Fissile mudstone (primarily clay minerals and silt-sized quartz)
Fossilized Sea Urchin (Echinoid)
Echinoidea (Class) - likely replaced by Calcite or Quartz
Chert (Flint)
Microcrystalline Quartz (SiO2)
Chert (Jasper)
Microcrystalline Quartz (SiO2)
Chert
Microcrystalline Quartz (SiO2)
Sandstone (Ferruginous)
Arenite (with Iron Oxide)
Sandstone
Arenite (SiO2 predominantly)
Fossil Shell Fragment (possibly Brachiopod or Bivalve)
Calcium Carbonate (CaCO3) - Phylum Brachiopoda or Mollusca
Brown Chert
Microcrystalline Quartz (SiO2)
Chert (Common Opal or Chalcedony)
Microcrystalline Quartz (SiO2)
Crinoid Fossil in Limestone
Crinoidea fossil (stalk segments) in Calcium Carbonate (CaCO3) matrix
Chert (varietal: Flint/Jasper)
Silicon Dioxide (SiO2)
Chert (Siltstone-Chert mixture)
Microcrystalline Quartz (SiO2)
Chert (Flint)
Microcrystalline Quartz (SiO2)
Sandstone
Arenite
Chert Arrowhead
Microcrystalline Quartz (SiO2)
Sandstone/Quartzite
Sedimentary Rock (composed mainly of SiO2)
Sandstone (Quartzite-rich)
Clastic sedimentary rock (SiO2 primarily)
Sandstone (with minor quartz and possible clay components)
Clastic Sedimentary Rock (SiO2 dominated)
Sandstone
Clastic sedimentary rock (primarily SiO2)
Chert (Jasper)
Silicon Dioxide (SiO2)
Chert (White/Gray variety)
Silicon Dioxide (SiO2 / Cryptocrystalline Quartz)
Chert / Jasper
Silicon Dioxide (SiO2)
Geode (unopened) or Calcareous Nodule
Siliceous or Calcareous Concretion/Nodule
Sandstone
Arenite (SiO2 primarily)
Sandstone (Iron-stained)
Arenite (primarily SiO2 with Fe2O3 staining)
Dalmatian Jasper
Peralkaline rhyolite with arfvedsonite inclusions