Red Siltstone
Siltstone (composed mainly of SiO2 and Fe2O3)
sedimentary
Category
Sedimentary (Man Made Composite)
Browse sedimentary (man made composite) specimens identified by the Rock Identifier community.
Sandstone
Arenite (primarily Quartz SiO2)
sedimentary
Sandstone (Ferruginous)
Arenite (with high iron oxide content)
sedimentary
Sandstone (with Iron concretions/staining)
Arenite (composed primarily of Quartz and Feldspar with Iron Oxide cement)
sedimentary
Sandstone (Ferruginous)
Arenite with Iron Oxide (Limonite/Hematite) coating
sedimentary
Sandstone (likely Siltstone variety)
Arenite / Siltstone (primary mineral SiO2)
sedimentary
Sandstone (with Iron Staining)
Clastic sedimentary rock (primarily Quartz with Fe2O3 staining)
sedimentary
Sandstone (Ferruginous)
Ferruginous Sandstone (SiO2 with Fe2O3/FeO(OH) cement)
sedimentary
Chert (Nodule)
Silicon dioxide (SiO2) - Cryptocrystalline Quartz
sedimentary
Chert (specifically Flint or Jasper variant)
Chert (Siliceous rock composed of microcrystalline Quartz, SiO2)
sedimentary
Specular Hematite with Pyrite
Iron Oxide (Fe2O3) with Iron Sulfide (FeS2)
mineral
Shale with Plant Fossils / Carbonaceous Shale
Laminated Mudrock (Siliciclastic)
sedimentary
Chert
Chert (microcrystalline quartz, SiO2)
Sedimentary
Ferruginous Sandstone (Ironstone)
Sedimentary rock with high iron oxide content (Fe2O3 / FeO(OH))
sedimentary
Greenstone (Greywacke or Nephrite Jade variant)
Metamorphosed mafic igneous or sedimentary rock (e.g., Actinolite-Chlorite Schist)
metamorphic
Druzy Quartz on Matrix (likely Limestone or Sandstone)
Silicon Dioxide (SiO2) with various trace impurities
Mineral on Sedimentary Rock
Red Sandstone
Clastic sedimentary rock (primarily SiO2 with Fe2O3 iron oxide staining)
sedimentary
Anthracite Coal
Anthracite (Carbon based)
metamorphic
Dalmatian Stone
Dalmatian Jasper (Aplitic Rock)
igneous
Ironstone concretion / Limonitic Sandstone
Goethite/Hematite Cemented Sandstone (Hydrated Iron Oxide)
sedimentary
Quartz (likely) or a Quartzite Pebble
Silicon dioxide (SiO2) for quartz. If it's quartzite, it's a metamorphic rock primarily composed of quartz.
Mineral, specifically a detrital grain
Coquina
Coquina (a type of limestone)
Sedimentary
Pyrite
Iron Sulfide (FeS2)
mineral
Chert (varietal: Flint/River Pebble)
Cryptocrystalline Quartz (SiO2)
sedimentary
Greywacke with Quartz Veins
Lithic Sandstone (Greywacke) with SiO2 inclusions
sedimentary
Bauxite
Bauxite (Al2O3·nH2O)
sedimentary
Chert / Flint
Microcrystalline Quartz (SiO2)
sedimentary
Polygenetic Conglomerate (Puddingstone)
Conglomerate (SiO2 matrix with mixed clasts)
sedimentary
Petrified Wood
Silicified Wood (primarily SiO2)
sedimentary
Ironstone Concretion (Limonite/Goethite)
Ironstone (primarily FeO(OH)·nH2O)
sedimentary
Chert (White/Gray variety)
Chert (SiO2)
sedimentary
Jasper (specifically a banded or dark variety)
Silicon Dioxide (SiO2) with impurities
sedimentary
Fossilized Bone Fragment
Permineralized Vertebrate Fossil (Hydroxyapatite replaced by Minerals)
sedimentary
Chert (Jasper/Iron-stained Quartzite)
Silicon Dioxide (SiO2)
sedimentary
Chert (specifically Flint or Gray Chalcedony)
Microcrystalline Quartz (SiO2)
sedimentary
Banded Chert
Silicon Dioxide (SiO2) - Microcrystalline Quartz
sedimentary
Chert (Novaculite Variety)
Microcrystalline Quartz (SiO2)
sedimentary
Oolite or Oolitic Limestone
Oolitic Limestone (Principal mineral: Calcite, CaCO3)
sedimentary
Chert (Jasper/Flint variety)
Microcrystalline Quartz (SiO2)
sedimentary
Chert with Asphaltum (or Tar)
Silica (SiO2) with natural Bitumen/Asphaltum
sedimentary
Pyrite
Iron Pyrite (FeS2)
Mineral
Chert
Chert (SiO2)
sedimentary