Petrified Wood
Silicified wood (Quartz/Chalcedony/Opal)
Category
Browse organic mineraloid and mineral specimens identified by the Rock Identifier community.
Petrified Wood
Silicified wood (Quartz/Chalcedony/Opal)
Red Jasper
Quartz (SiO2) with iron oxide inclusions
Petrified Wood
Silicified Wood (SiO2)
Orthoceras Fossil in Limestone
Orthoceras (extinct genus of cephalopods) in Carboniferous or Devonian Limestone
Chert (Jasper/Limonitic Chert)
Microcrystalline Quartz (SiO2)
Petrified Wood
Silicified Wood (SiO2)
Ferruginous Chert
Microcrystalline Quartz (SiO2) with Iron Oxides
Fossilized Crinoid Stem Segment
Crinoid (Phylum Echinodermata, Class Crinoidea)
Petrified Wood
Silicified Wood (SiO2)
Chert (often called Flint)
Chert (Microcrystalline Silicon Dioxide, SiO2)
Red Jasper
Red Jasper (SiO2 with Fe2O3 inclusions)
Amethyst
Amethyst (Silicon Dioxide - SiO2 with ferric iron impurities)
Moonstone (Orthoclase Feldspar)
(K,Na)AlSi3O8
Tiger's Eye
Silicon Dioxide (SiO2) with iron oxide inclusions
Tiger Iron
Tiger Iron (composite of Tiger's Eye, Red Jasper, and Hematite)
Libyan Desert Glass
Tektite (high-silica impact glass), SiO2
Iron Slag (Industrial Byproduct)
Anthropogenic Vitrification Product/Ferrous Slag
Tiger's Eye
Pseudomorph of quartz after crocidolite (SiO2 with iron oxide inclusions)
Clear Quartz
Silicon Dioxide (SiO2)
Jasper-Agate Breccia
Silicon Dioxide (SiO2) with iron oxide inclusions
Chert (Flint Pebbles)
Microcrystalline Quartz (SiO2)
Chert (often called Flint or Jasper)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Jasper (Brown Iron-Rich Variety)
Silicon Dioxide (SiO2) with Fe2O3 (Iron Oxide/Crystalline Quartz)
Banded Chert
Cryptocrystalline Quartz (SiO2)
Banded Chert (Flint/Jasper variety)
Microcrystalline Quartz (SiO2)
Sandstone (likely Fossilized Wood or Concrete Simulacrum)
Arenite / Silicified Wood / Anthropogenic Concrete
Amber
Succinicum (Organic polymer, largely C10H16O)
Petrified Wood
Silicified Wood (primarily SiO2)
Red Slag Glass
Amorphous Silica (Industrial byproduct with metallic oxide dopants)
Sandstone (likely Arkose or Lithic)
Clastic sedimentary rock (SiO2 + impurities)
Septarian Nodule or Mud Crack Fossil
Septarian Nodule (Concretion)
Limestone (Concretionary or Tufa)
Calcium Carbonate (CaCO3)
Petrified Wood
Silicified Wood (SiO2)
Pyrite Geode (Sparkling Druzy)
Iron Sulfide (FeS2) in Sedimentary Nodule
Pearl
Biogenic Calcium Carbonate (Aragonite/Calcite), CaCO3
Petrified Wood
Silicified Wood (primarily SiO2)
Shale
Shale (comprised mostly of clay minerals and quartz)
Petrified Wood
Silicified Wood (SiO2)
Chert (containing Iron Oxide)
Microcrystalline Quartz (SiO2)
Chert (Flint)
Microcrystalline Quartz (SiO2)
Sandstone Concretion
Sedimentary Clastic Rock (Silicate-rich)
Chert (with Limestone matrix)
Silicon dioxide (SiO2)