Chert (Arrowhead Preform or Flake)
Microcrystalline Quartz (SiO2)
Category
Browse organic materia (not a rock or mineral) specimens identified by the Rock Identifier community.
Chert (Arrowhead Preform or Flake)
Microcrystalline Quartz (SiO2)
Shale (or Mudstone)
Siltstone/Argillite (composed mainly of clay and silt-sized particles)
Milky Quartz with Country Rock contact
Silicon Dioxide (SiO2) in contact with Metamorphic/Igneous rock
Smoky Quartz and Chalcedony Geode Fragment
Silicon Dioxide (SiO2)
Amber (Rough)
Amber (Fossilized Tree Resin, succinite)
Moss Agate
Cryptocrystalline Quartz (SiO2 with Manganese or Iron Oxide inclusions)
Sandstone
Arenite (primarily SiO2)
Petrified Wood
Silicified Wood (SiO2)
Chert (Jasper/Limonitic Chert)
Microcrystalline Quartz (SiO2)
Petrified Wood
Silicified Wood (SiO2)
Chert (specifically Blue Chert or Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Banded Slate or Siltstone with Quartz/Calcite Veins
Protolith-derived Siltstone or Slate (varies based on degree of metamorphism)
Fossilized Shark Tooth
Scapanorhynchus (Sand Tiger Shark relative)
Chert (often called Flint in this context)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Quartz Vein in Host Rock
Hydrothermal Quartz (SiO2) in Slates/Schists
Granodiorite
Granodiorite (Intermediate intrusive igneous rock)
Petrified Wood
Silicified Wood (SiO2 as Quartz/Chert/Chalcedony)
Jasper (Brown Iron-Rich Variety)
Silicon Dioxide (SiO2) with Fe2O3 (Iron Oxide/Crystalline Quartz)
Moss Agate
Silicon Dioxide with inclusions (SiO2 + impurities)
Petrified Wood
Silicified Wood (primarily SiO2)
Petrified Wood
Silicified wood (Quartz/Chalcedony replacement of organic matter)
Fossilized Crab Carapace (Concretion)
Decapoda (fossil), typically preserved in calcite or siderite concretion
Moqui Marbles
Iron Oxide Concretion (Hematite/Goethite)
Petrified Wood
Silicified wood (primarily SiO2)
Pearl
Organic gemstone (Calcium carbonate / CaCO3 + Conchiolin)
Sandstone
Arenite (primarily SiO2)
Chert (with Quartz vein/coating)
Microcrystalline Quartz (SiO2)
Greywacke (likely)
Greywacke (a type of sandstone)
Jasper (Green/Yellow Moss Jasper)
Silicon Dioxide (SiO2)
Chert (often called Flint or Jasper)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Sandstone (likely Greywacke or Lithic Sandstone)
Arenite / Wacke
Banded Agate (specifically Moss Agate or Plume Agate variety)
Silicon Dioxide (SiO2) - Cryptocrystalline Quartz
Quartz (Druzy)
Silicon Dioxide (SiO2)
Chert (Mudstone)
Microcrystalline Quartz (SiO2)
Chert (varietal known as Jasper or Flint)
Silicon Dioxide (SiO2)
Fossiliferous Limestone
Limestone (CaCO3 - Calcium Carbonate)
Petrified Wood
Silicified Wood (SiO2)
Petrified Wood
Silicified Wood (SiO2)
Wishing Stone (Basalt or Siltstone with Quartz/Calcite Vein)
Basalt (SiO2+MgO+FeO) or Siltstone with a Quartz (SiO2) or Calcite (CaCO3) vein
Ferruginous Sandstone (with possible trace fossils)
Arenite with Iron-Oxide Cement (SiO2 with Fe2O3)
Amber Inlay Jewelry
Fossilized Resin (C10H16O)
Chert (with Limestone matrix)
Silicon dioxide (SiO2)