Obsidian
Volcanic glass (mainly SiO2 with inclusions)
Category
Browse sedimentary (or mineraloid) specimens identified by the Rock Identifier community.
Obsidian
Volcanic glass (mainly SiO2 with inclusions)
Mahogany Obsidian
Volcanic glass containing Hematite or Magnetite (SiO2 + Fe2O3)
Obsidian
Obsidian (Volcanic Glass)
Obsidian
Amorphous volcanic glass (primarily SiO2)
Snowflake Obsidian
Spherulitic Volcanic Glass (primarily SiO2 with Cristobalite inclusions)
Snowflake Obsidian
Volcanic Glass with Cristobalite inclusions (70–75% SiO2)
Black Obsidian
Obsidian (Amorphous Silicon Dioxide)
Snowflake Obsidian
Volcanic Glass with Cristobalite Inclusions
Green Opal
Hydrated amorphous silica (SiO2·nH2O) with inclusions
Amber (Copal)
Succinate (Fossilized Resin)
Amber
Succinite (fossilized tree resin)
Amber
Succinite (Fossilized Tree Resin)
Amber
Succinite (fossilized resin)
Cobalt Glass Slug (Man-made Glass)
Amorphous Silica with Cobalt Oxide (SiO2 + CoO)
Shungite
Carbonaceous rock (primarily amorphous carbon)
Cullet Glass (Slag)
Amorphous Silicon Dioxide (Man-made)
Tektite (Indochinite)
Impact Glass (SiO2 + Al2O3)
Slag (Industrial Glass)
Anthropogenic Amorphous Vitreous Silicate
Amber
Succinite (Resinite)
Pearl
Calcium carbonate (CaCO3) - mainly Aragonite with Conchiolin
Amber
Amber (Succinite), fossilized tree resin
Conch Pearl
Calcareous concretion (CaCO3)
Amber
Succinite (approximate formula C10H16O)
Tektite (Indochinite)
Tektite (SiO2 + Al2O3)
Sea Glass (Frosted Quartz/Glass)
Amorphous Silicon Dioxide (SiO2)
Amber
Succinite (approximate formula C10H16O)
Amber
Succinite
Pearls
Aragonite (calcium carbonate) and Conchiolin
Amber
Succinite
Amber
Succinite (C10H16O)
Amber
Succinite (Fossilized Tree Resin)
Fulgurite
Liesegang (Fulgurite)
Amber
Succinite (specifically for Baltic amber); approximate formula C10H16O
Amber (Raw)
Succinite (Fossilized Resin)
Amber
Succinurite (C10H16O)
Amber
Succinite (Carbon-based organic compound; approximate formula C10H16O)
Amber (with potentially inclusions)
Succinite (Fossilized Tree Resin)
Fire Opal (in matrix)
Hydrated Silica (SiO2·nH2O)
Amber with Organic Inclusions
Succinite (fossilized resin)
Amber / Copal
Succinite (fossilized resin)
Amber
Succinite (Fossilized Tree Resin)
Amber
Succinite (C10H16O)