Petrified Wood
Silicified Wood (SiO2)
Category
Browse organic mineraloid and mineral specimens identified by the Rock Identifier community.
Petrified Wood
Silicified Wood (SiO2)
Fossil Coral (Favosites Honeycomb)
Favosites (Genus), Phylum Cnidaria, Class Anthozoa
Petrified Wood
Silicified Wood (SiO2)
Barite Rose on Marcasite
Barium Sulfate (BaSO4) on Iron Sulfide (FeS2)
Blue Calcite
Calcium Carbonate (CaCO3)
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
Septarian Nodule (Septarian Dragon Stone)
Septarian Concretion (Composition: Calcite, Aragonite, and Limestone/Clay)
Chert (Arrowhead Fragment)
Microcrystalline Quartz (SiO2)
Ironstone Concretion
Siderite or Hematite Concretion
Chert (Nodule)
Silicon Dioxide (SiO2)
Chert (Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Liesegang Ring Siltstone
Siltstone with iron oxide Liesegang bands
Agate (Turtle Carving)
Agate (Cryptocrystalline variety of Silica, SiO2)
Chert (Flint)
Chert (Cryptocrystalline Silicon Dioxide, SiO2)
Shale or Siltstone
Sedimentary Clastic Rock (Variable mineral composition including quartz and clay minerals)
River Stone (likely Mudstone or Siltstone)
Lutite (Clastic sedimentary rock composed of clay and silt-sized particles)
Petrified Wood
Silicified Wood (primarily SiO2 - Silicon Dioxide)
Dyed Agate Slice
Silicon Dioxide (SiO2) - variety of Chalcedony
Chert (Flint nodule)
Silicon dioxide (SiO2)
Chert / Flint
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (Green variety)
Microcrystalline Opaline/Quartz (SiO2)
Chert (variations include Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Black Onyx
Cryptocrystalline Quartz (SiO2 with organic/iron impurities)
Blue Agate (Tumbled and Dyed)
Silicon Dioxide (SiO2) with likely organic dyes
Red Jasper
Silicon dioxide (SiO2) with iron oxide (Fe2O3) inclusions
Picture Jasper
Silicon Dioxide (SiO2) with iron oxide and clay inclusions
Chert (Iron-stained)
Microcrystalline Quartz (SiO2)
Chert (Flint Nodules)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Yellow Chert (Jasper)
Microcrystalline Quartz (SiO2)
Ironstone Concretion (Ironstone Gourd)
Limonite/Goethite Concretion (FeOO(H))
Petrified Wood
Silicified wood (primarily Silicon Dioxide - SiO2)
Chert (often called Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (varieties include Flint or Jasper)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Mica Schist
Foliated Metamorphic Rock (rich in Muscovite or Biotite)
Fluorite
Calcium Fluoride (CaF2)
Amethyst Geode
Silicon Dioxide (SiO2) with trace Iron (Fe3+) impurities
Milky Quartz with Chlorite/Mica inclusions
Silicon Dioxide (SiO2) with phyllosilicate inclusions
Carnelian
Carnelian Chalcedony (SiO2 with Iron Oxide impurities)
Libyan Desert Glass
Impact-melt silica glass (SiO2 + traces of Al, Fe, Ti)
Dendritic Opal (Common Opal)
Amorphous Hydrated Silica (SiO2·nH2O) with Manganese or Iron Oxide inclusions
Quartz Geode
Silicon Dioxide (SiO2)
Petrified Wood
Silicified Wood (SiO2)