Sandstone
Arenite
Category
Browse organic (sedimentary context) specimens identified by the Rock Identifier community.
Sandstone
Arenite
Chert / Flint
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (Tan/Brown variety)
Chert (Microcrystalline Quartz, SiO2)
Chert (Cherty Limestone or Flint)
Microcrystalline Silica (SiO2)
Chert (Iron-stained)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (Jasper/Flint variety)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (Nodular or Massive Variety)
Cryptocrystalline Quartz (SiO2)
Chert (Jasper/Flint variety)
Microcrystalline Quartz (SiO2)
Chert with Quartz/Calcite Vein
Microcrystalline Silica (SiO2)
Petrified Wood
Silicified Wood (primarily SiO2 - Silicon Dioxide)
Fossil Plant Impression (Calamites)
Calamites sp. (Tracheophyta: Equisetopsida)
Petrified Wood
Silicified Wood (SiO2)
Petrified Wood
Silicified Wood (SiO2)
Chert (variations include Flint/Jasper)
Cryptocrystalline Silicon Dioxide (SiO2)
Chert (Jasper/Flint variety)
Microcrystalline quartz (SiO2)
Chert (specifically Flint or Jasper variant)
Microcrystalline Quartz (SiO2)
Chert (varietal Flint or Jasper)
Microcrystalline Quartz (SiO2)
Fossiliferous Limestone (Coquina / Shell Limestone)
Biogenic Limestone (CaCO3)
Petrified Wood
Silicified wood (primarily SiO2)
Chert (containing Fossil Inclusions)
Microcrystalline Quartz (SiO2)
Petrified Wood (Agatized/Silicified Wood)
Silicified Paleoxylon (primarily SiO2)
Chert Pebble
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (Jasper/Flint variety)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (varieties include Flint and Jasper)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (Black Chert/Flint)
Cryptocrystalline Quartz (SiO2)
Fossilized Crinoid Stem Segment
Crinoid (Phylum Echinodermata, Class Crinoidea)
Chert (Flint)
Microcrystalline Quartz (SiO2)
Petrified Wood
Silicified Wood (primarily Quartz/Chalcedony, formula SiO2)
Fossiliferous Limestone
Biogenic Limestone (Calcium Carbonate, CaCO3)
Chert (Green Chert or Jasper)
Microcrystalline Quartz (SiO2)
Crinoid Fossil in Limestone
Crinoid (Class Crinoidea) in Fossiliferous Limestone (CaCO3)
Small seashell fossil or shell fragment
Likely calcium-carbonate shell material, chiefly aragonite or calcite; exact species indeterminate
Chert Nodule
Microcrystalline Quartz (SiO2)
Limestone with Calcite Veining
Sedimentary Carbonate Rock (CaCO3)
Limestone (Porous/Travertine variant)
Sedimentary Calcium Carbonate (CaCO3)
Fossilized Coral
Rugosa / Scleractinia (Agatized or Calcitized Coral)
Petrified Wood
Silicified Wood (SiO2)
Shale or Mudstone (Based on appearance)
Shale (fine-grained, laminated fissile sedimentary rock) / Mudstone (fine-grained, non-fissile sedimentary rock)
Petrified Wood
Silicified Wood (SiO2)
Chalk
Calcium Carbonate (CaCO3)
Honey calcite (orange calcite)
Calcite, calcium carbonate (CaCO₃)
Ironstone Concretion / Limonite Node
Ferruginous Sedimentary Rock (composed primarily of Limonite FeO(OH)·nH2O and Goethite)