Petrified Wood
Silicified Wood (SiO2)
Category
Browse organic (non geological) specimens identified by the Rock Identifier community.
Petrified Wood
Silicified Wood (SiO2)
Black Obsidian
Obsidian (Volcanic Glass), primarily SiO2 (Silicon Dioxide) with impurities
Petrified Wood
Silicified Wood (primarily SiO2 - Silicon Dioxide)
Chert (variations include Flint or Jasper)
Silicon Dioxide (SiO2)
Jasper
Silicon Dioxide (SiO2) with iron oxide impurities
Chert (Jasper variation)
Chert (SiO2)
Obsidian
Obsidian (principally SiO2 with MgO and Fe3O4)
Chert (with Quartz vein)
Chert (Silicon Dioxide, SiO2)
Petrified Wood
Silicified Wood (SiO2)
Goldstone (Red/Brown)
Aventurine Glass (SiO2 with Copper inclusions)
Snowflake Obsidian
Obsidian with Cristobalite inclusions (70–75% SiO2)
Snowflake Obsidian
Vitreous volcanic silicate (SiO2 with Cristobalite inclusions)
Obsidian
Volcanic Glass (SiO2 + impurities)
Petrified Wood
Silicon Dioxide (SiO2) permineralized organic matter
Sandstone (likely a river or beach pebble)
Sandstone (a clastic sedimentary rock)
Petrified Wood
Silicified Wood (SiO2)
Chert (Arrowhead variety)
Chert (SiO2)
Red Jasper
Red Jasper (variety of Chalcedony, SiO₂)
Chert (specifically a fragment with Desert Varnish)
Microcrystalline quartz (SiO2)
Conglomerate
Conglomerate (Sedimentary Clastic Rock)
Garnet (Almandine variety)
Almandine, Fe3Al2(SiO4)3
Obsidian (in jewelry setting)
Volcanic Glass (Amorphous Silica)
Moss Agate
Silicon Dioxide (SiO2) with inclusions of manganese or iron oxides
Obsidian
Obsidian (principally SiO2/Silicon dioxide)
Obsidian
Obsidian (Volcanic Glass)
Chert (Flint)
Chert (Cryptocrystalline variety of Quartz, SiO2)
Moss Agate and Hematite
Silica (SiO2) with fibrous inclusions of Manganese or Iron; Hematite (Fe2O3)
Petrified Wood
Silicified Wood (primarily SiO2)
Septarian Nodule or Mud Crack Fossil
Septarian Nodule (Concretion)
Chert (variations include Flint or Jasper)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Blue Sapphire (Ceylon)
Corundum (Al2O3) with traces of Iron and Titanium
Gold Sheen Obsidian
Volcanic Glass (SiO2 + Fe3O4 / Gas Inclusions)
Petrified Wood
Silicified Wood (primarily SiO2)
Grey and White Chert (Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (specifically Tan/Yellow Chert)
Chert (Microcrystalline or Cryptocrystalline Silica, SiO2)
Chert (Quartz Variety)
Microcrystalline Silica (SiO2)
Petrified Wood
Silicified Wood (primarily SiO2)
Ambergris
Ambergris (Coprolite-adjacent organic substance)
Obsidian
Obsidian (principally SiO2)
Petrified Wood
Silicified Wood (primarily SiO2 - Silicon Dioxide)
Petrified Wood
Silicified Wood (SiO2)
Chert (Arrowhead/Tool variety)
Microcrystalline Quartz (SiO2)