Carnelian (Chalcedony)
Cryptocrystalline Quartz (SiO2) with Iron Oxide impurities
Category
Browse sedimentary rock specimens identified by the Rock Identifier community.
Carnelian (Chalcedony)
Cryptocrystalline Quartz (SiO2) with Iron Oxide impurities
Ferruginous Quartz
Silicon Dioxide (SiO2) with Hematite/Limonite impurities
Gneiss
Gneiss (High-grade Metamorphic Rock)
Jasper Agate (specifically Brecciated Jasper)
Silicon Dioxide (SiO2) with iron oxide and clay impurities
Gneiss (River Cobble)
Gneiss (Foliated Metamorphic Rock)
Hag Stone
Perforated Chert (Microcrystalline Silica, SiO2)
Chert (Flint Nodules)
Cryptocrystalline Quartz (SiO2)
Greywhacke (River Pebble)
Graywacke (immature sandstone)
Sandstone (Quartzite Pebble)
Arenite / Metamorphosed Sandstone (SiO2)
Chert (and Flint variant)
Chert (SiO2)
Chert (Iron-stained)
Microcrystalline Quartz (SiO2)
Liesegang Banded Sandstone (Wonderstone)
Ferruginous Sandstone with Liesegang Rings
Limestone (Weathered)
Calcium Carbonate (CaCO3)
Sandstone (likely Graywacke or Lithic Sandstone)
Arenite / Wacke (SiO2 based with lithic fragments)
Green Jasper with Quartz veins
Jasper (Silicon Dioxide, SiO2)
Sandstone (specifically Cross-bedded Sandstone)
Arenite (composed primarily of SiO2)
Arkosic Sandstone
Arkose
Chert (Flint)
Chert (Silicon Dioxide, SiO2)
Petrified Wood
Silicified Wood (primarily Quartz/Chalcedony, formula SiO2)
Brachiopod Fossil (Spiriferid)
Order Spiriferida (Phylum Brachiopoda); mineralized as Calcite (CaCO3) or Chert (SiO2)
White Agate (Chalcedony)
Silicon Dioxide (SiO2)
Favosites Fossil (Honeycomb Coral)
Favosites sp. (Extinct genus of tabulate coral)
Jasper (Red/Brown Variety)
Jasper (Silicon Dioxide, SiO2 plus Iron Oxide impurities)
Jasper
Silicon dioxide (SiO2) with iron impurities
Quartz on Schist
Silicon Dioxide (SiO2) on Foliated Metamorphic Rock
Gneiss
Gneiss (High-grade metamorphic rock)
Sandstone with Liesegang Rings
Arenite with secondary Iron oxide (Limonite/Goethite) precipitation
Sandstone (Red Sandstone / River Stone)
Arenite (composed primarily of Quartz, SiO2, with Iron Oxide cementation)
Petrified Wood
Silicified Wood (SiO2)
Chert (specifically tan/pink variety)
Silicon Dioxide (SiO2)
Boulder Opal
Precious Opal in Ironstone (Amorphous Hydrated Silica, SiO2·nH2O)
Quartz Geode
Crystalline Silicon Dioxide (SiO2) in Geode form
Chert (specifically Gray/Tan Bedded Chert)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Gneiss
Gneiss (High-grade regional metamorphic rock)
Gneiss
Gneiss
Chert (often called Jasper in this color)
Microcrystalline quartz (SiO2)
Ferruginous Chert (Jasper)
Silicon Dioxide (SiO2) with iron oxide inclusions
Oolite (Ooid Limestone)
Ooidal Limestone (comprised of CaCO3)
Coquina
Coquina (Bioclastic Limestone)
Chert (Jasper/Flint variety)
Microcrystalline Quartz (SiO2)
Crinoid Fossil Stem Segment
Class Crinoidea (Echinodermata)
Chert (Yellow Jasper variant)
Microcrystalline Quartz (SiO2)