Black obsidian (probable)
Volcanic glass; primarily SiO₂-rich rhyolitic composition
Category
Browse non geological specimens identified by the Rock Identifier community.
Black obsidian (probable)
Volcanic glass; primarily SiO₂-rich rhyolitic composition
Quartzite
Metamorphic rock composed primarily of quartz (SiO2)
Opalite (Synthetic Opalized Glass)
Synthetic Silicon Dioxide (SiO2) glass
Quartzite
Metamorphic Quartzite (SiO2)
Quartzite
Quartzite (primarily SiO2)
Obsidian
Obsidian (Volcanic Glass, SiO2)
Green cabochon gemstone pendant
Indeterminate; likely dyed green turquoise, chrysoprase, or opaque beryl set with blue/clear accent stones
Black Obsidian
Volcanic Glass (SiO2 with impurities)
Obsidian
Volcanic Glass (SiO2)
Quartzite
Quartzite (Metamorphosed Quartz Sandstone)
Slag
Ferrous Slag (Amorphous calcium-magnesium-aluminum silicates)
Black Obsidian
Volcanic Glass (Amorphous Silicon Dioxide SiO2)
Limonite (Yellow Ochre)
Limonite (an amorphous mixture of hydrated iron oxides, primarily FeO(OH)·nH2O)
Rounded gray river pebble, likely basalt or andesite
Fine-grained mafic to intermediate volcanic rock; commonly basalt (plagioclase + pyroxene, sometimes olivine)
Amber
Succinite (specific to Baltic amber), fossilized tree resin
Obsidian
Obsidian (Volcanic Glass, SiO2 + impurities)
Obsidian
Obsidian (Volcanic glass), SiO2 (major component)
Quartzite
Metamorphic Quartzite (SiO2)
Shale
Shale (clastic sedimentary rock composed of silt and clay-sized particles)
Conglomerate
Conglomerate (SiO2, Al2O3, Fe2O3, CaCo3)
Chert (Iron-stained)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Quartzite
Metamorphic rock predominantly composed of Quartz (SiO2)
Quartzite
Metamorphic Quartzite (SiO2)
Quartzite
Metamorphic Quartzite
Black Obsidian
Obsidian (Volcanic Glass), primarily SiO2 (Silicon Dioxide)
Quartzite
Metamorphic Quartzite (SiO2)
Rounded quartzite pebble
Quartzite, predominantly crystalline SiO₂
Snowflake Obsidian
Volcanic glass containing Spherulites of Cristobalite (SiO2)
Obsidian
Volcanic glass (SiO2 - Silicon Dioxide with impurities)
Snowflake Obsidian
Obsidian (volcanic glass) with Cristobalite inclusions
Chert Nodule (Flint)
Silicon Dioxide (SiO2)
Obsidian
Volcanic glass
Quartzite
Quartzite (primarily SiO2)
Black Obsidian with white veins
Volcanic Glass (70–75% SiO2)
Barite
Barium Sulfate (BaSO4)
Obsidian
Volcanic Glass (mostly SiO2)
Obsidian
Volcanic glass (SiO2 - Silicon Dioxide with impurities)
Obsidian
Obsidian (Volcanic Glass)
Amber
Succinite (Carbon-based organic compound; approximate formula C10H16O)
Quartzite
Quartzite (composed primarily of SiO2)
Obsidian
Obsidian (Volcanic Glass, SiO2)
Quartzite
Metamorphic Quartzite (SiO2)