Petrified Wood
Silicified Wood (primarily SiO2)
Category
Browse sedimentary or igneous fragment specimens identified by the Rock Identifier community.
Petrified Wood
Silicified Wood (primarily SiO2)
Opal
Hydrated Silica (SiO2·nH2O)
Opal
Hydrated Silica (SiO2·nH2O)
Sandstone with Concretions / Liesegang Rings
Arenite with iron oxide banding
Pyrite
Iron Sulfide (FeS2)
Sandstone Cobble
Arenite (Secondary classification based on grain size)
Fluorite (Rainbow, Purple-Blue Tumbled)
Calcium Fluoride (CaF2)
White Quartz Pebble
Quartz (Silicon Dioxide, SiO2)
Rough Ruby
Corundum (Al2O3 with Chromium impurities)
Green Fluorite
Fluorite (Calcium Fluoride - CaF2)
Sandstone (Cross-bedded Drill Core)
Clastic Sedimentary Rock (primarily SiO2)
Sandstone (Weathered Cobble)
Clastic Sedimentary Rock (primarily SiO2)
Fossiliferous Sandstone (with Brachiopod or Bivalve mold)
Clastic Sedimentary Rock with Macrofossil Mold
Sandstone Concretion with Quartz Center
Sedimentary Clastic Rock (SiO2 matrix with Quartz core)
Sandstone (Ferruginous)
Arenite (primarily SiO2 with Fe2O3 staining)
Red Sandstone
Arenite (primarily Quartz SiO2 with Hematite Fe2O3 cement)
Sandstone (Ferruginous)
Arenite (Fe-rich)
Red Sandstone
Arenite (with Iron Oxide cement)
Red Sandstone
Arenite (primarily composed of SiO2 with Fe2O3 cement)
Orthoclase Feldspar
Orthoclase (KAlSi₃O₈)
Native Gold (in the form of jewelry)
Gold (Au)
River Cobble (likely Quartzite or Limestone)
SiO2 (Quartzite dominant) or CaCO3 (Limestone dominant)
Amethyst
Silicon Dioxide (SiO2) with iron impurities
Chert (Flint)
Microcrystalline Quartz (SiO2)
Sandstone Beach Pebble
Clastic Sedimentary Rock (primarily Quartz with Iron Oxide coating)
Sandstone Clast
Arenite (primarily SiO2)
Sandstone (Ferruginous)
Arenite (with high iron oxide content)
Red Sandstone
Arenite (primarily SiO2 with hematite/iron oxide coating)
Sandstone
Arenite (primarily SiO2)
Sandstone
Arenite (primarily SiO2)
Sandstone (specifically Arkose or Ferruginous Sandstone)
Sandstone (SiO2 with iron oxide inclusions)
Ferruginous Sandstone (Ironstone)
Clastic sedimentary rock (SiO2 with Fe2O3/FeO(OH) cement)
Sandstone (with Iron concretions/staining)
Arenite (composed primarily of Quartz and Feldspar with Iron Oxide cement)
Sandstone (Ferruginous)
Ferruginous Sandstone (SiO2 with Fe2O3/FeO(OH) cement)
Red Sandstone
Clastic sedimentary rock (primarily SiO2 with Fe2O3)
Fossiliferous Chert (with Brachiopod or Mollusk fragments)
Silicon dioxide (SiO2) with Calcium Carbonate (CaCO3) inclusions
Sandstone
Arenite (SiO2 based clastic rock)
Sandstone (Red Sandstone / River Stone)
Arenite (composed primarily of Quartz, SiO2, with Iron Oxide cementation)
Petrified Wood
Silicified Wood (primarily SiO2)
Green Fluorite
Calcium Fluoride (CaF2)
Quartz (Iron-stained)
Silicon Dioxide (SiO2)
Blue Calcite
Calcium Carbonate (CaCO3)