Petrified Wood (Silicified Fossil)
Silicified Wood (SiO2)
sedimentary
Category
Anthropogenic (Man Made Material Processed By Nature)
Browse anthropogenic (man made material processed by nature) specimens identified by the Rock Identifier community.
Petrified Wood
Silicified Wood (primarily Quartz/Chalcedony, formula SiO2)
mineral
Serpentinite
Serpentinite (composed primarily of serpentine-group minerals like antigorite, chrysotile, and lizardite; chemical formula varies but generally Mg3Si2O5(OH)4)
Metamorphic Rock
Petrified Wood
Silicified wood (principally SiO2)
sedimentary
Shale or Argillite
Shale (fine-grained clastic sedimentary rock) or Argillite (low-grade metamorphic rock derived from shale)
Sedimentary or Metamorphic (low grade)
Slag Glass (Cullet Glass)
Amorphous Silica (Industrial byproduct)
mineral
Diamond
Diamond (carbon allotrope), C (chemical formula)
Mineral
Petrified Wood (Jet or Coalified Wood appearance)
Silicified wood (principally SiO2) or Carbonized Wood
sedimentary
Petrified Wood
Silicified Wood (primarily SiO2)
sedimentary
Petrified Dinosaur Bone (Gembone)
Agatized Dinosaur Bone
sedimentary
Chert (Nodular Chert)
Microcrystalline or Cryptocrystalline Silicon Dioxide (SiO2)
sedimentary
Grey River Pebble (Likely Quartz-rich or Limestone)
Clastic Sedimentary Rock (typically SiO2 or CaCO3 based)
sedimentary
Quartzite
Quartzite (SiO2)
metamorphic
Sandstone (likely Arkosic or Quartzose)
Arenite (SiO2 based with mineral inclusions)
sedimentary
Petrified Wood
Silicified Wood (primarily Chalcedony/Quartz, SiO2)
sedimentary
Pebble (likely Quartz or Chert)
SiO₂ (Silicon Dioxide) - referring to the likely main mineral composition, Quartz. If it's chert, the scientific name remains SiO₂ with a microcrystalline structure.
Sedimentary Rock
Petrified Wood
Silicified Wood (SiO2 as Quartz/Chert/Chalcedony)
sedimentary
Porphyritic Basalt (or Andesite) Pebble
Porphyritic Mafic Volcanic Rock
igneous
Banded Chert
Microcrystalline Quartz (SiO2)
sedimentary
Ferruginous Sandstone
Ferruginous Clastic Sedimentary Rock
sedimentary
Petrified Wood
Silicified Wood (SiO2)
sedimentary
Cubic Zirconia (Simulated Diamond)
Zirconium dioxide (ZrO2)
mineral
Sandstone Chert/Quartzite
Silicon Dioxide (SiO2) - Sedimentary Sandstone / Orthoquartzite
sedimentary
Quartz (specifically Citrine or Iron-stained Quartz)
Silicon Dioxide (SiO2)
mineral
Petrified Wood
Silicified Wood (primarily Quartz/Chalcedony, formula: SiO2)
sedimentary
Peridot (Olivine)
Magnesium Iron Silicate (Mg,Fe)2SiO4
mineral
Olivine
(Mg,Fe)2SiO4 (Magnesium Iron Silicate)
mineral
Petrified Wood
Silicified Wood / Chalcedony (SiO2)
mineral
Pink Granite
Phaneritic Felsic Igneous Rock (Granite, rich in Potassium Feldspar)
igneous
Chert / Flint
Cryptocrystalline Quartz (SiO2)
sedimentary
Tiffany Stone
Bertrandite Fluorite (CaF2 + Be4Si2O7(OH)2)
metamorphic
Chert / Flint
Chert (varieties include Flint)
Sedimentary
Red Sandstone
Arenite (with Iron Oxide cement)
sedimentary
Jasper (Petrified Wood Variety)
Silicon Dioxide (SiO2)
sedimentary
Turquoise and Red Coral
Turquoise: CuAl6(PO4)4(OH)8·4H2O; Red Coral: Corallium rubrum (organic gemstone)
mineral
Moss Agate
SiO2 (Silicon Dioxide) with dendritic inclusions
Mineral
Fossil Shell (Bivalve)
Phylum Mollusca, Class Bivalvia (typically composed of Calcium Carbonate / CaCO3)
sedimentary
Chert (Agate/Flint variant)
Microcrystalline Quartz (SiO2)
sedimentary
Serpentine, likely a variety of Chrysoprase (green chalcedony) or a similar translucent green mineral.
Serpentine Group Minerals (e.g., Antigorite, Lizardite) or Chalcedony (SiO2) with nickel impurities for Chrysoprase green.
mineral
River Pebble (Likely Quartzite or Chalcedony)
Silicon Dioxide (SiO2) - granular metamorphic variety
metamorphic
Sandstone (with Iron Staining)
Clastic sedimentary rock (primarily SiO2 with Fe2O3 staining)
sedimentary
Sugilite
Sugilite (KNa2(Fe,Mn,Al)2Li3Si12O30)
mineral