Black Obsidian
Obsidian (Volcanic Glass), primarily SiO2 (Silicon Dioxide)
Category
Browse non geological specimens identified by the Rock Identifier community.
Black Obsidian
Obsidian (Volcanic Glass), primarily SiO2 (Silicon Dioxide)
Black Opal
Amorphous Hydrated Silica (SiO2·nH2O)
Quartzite
Quartzite (composed primarily of SiO2)
Quartzite (River Stone)
Quartzite
Amber
Succinite
Obsidian
Volcanic Glass (Primary composition: SiO2 - Silicon Dioxide)
Rough Amber (likely Copal or immature Amber)
Organic gemstone / Succinite (if Baltic)
Coal (Anthracite or Bituminous)
Carbon (C) with varying hydrocarbon and mineral impurities
Tektite (Indochinite)
Tektite (High-silica natural glass, primarily SiO2 with Al2O3)
Amber
Succinite (fossilized resin)
Fossiliferous Limestone
Biogenic Limestone (Calcium Carbonate, CaCO3)
Ambergris
Ambergris (Coprolite-adjacent/Organic secretion)
Snowflake Obsidian
Spherulitic Volcanic Glass (primarily SiO2 with Cristobalite inclusions)
Red Quartzite
Quartzite (primarily SiO2)
Amber
Succinite (Resinite), C10-H16-O
Amber
Succinite (specifically for Baltic amber); approximate formula C10H16O
Quartzite River Rock
Quartzite (SiO2)
Quartzite
Quartzite (primarily SiO2)
Quartzite with inclusions
Quartzite (primarily SiO2)
Mahogany Obsidian
Volcanic glass containing Hematite or Magnetite (SiO2 + Fe2O3)
Obsidian
Obsidian (Volcanic Glass)
Quartzite (or Ferruginous Quartzite)
Metamorphosed Quartz Sandstone (SiO2 with Fe2O3 impurities)
Amber
Succinite (Fossilized Tree Resin) - C10H16O
Snowflake Obsidian
Volcanic Glass (spherulitic Obsidian) - SiO2 (with Cristobalite inclusions)
Mahogany Obsidian
Volcanic Glass (predominantly SiO2 with Fe2O3 inclusions)
Quartzite Pebble
Quartzite (primarily SiO2)
Fossiliferous Limestone (Coquina / Shell Bed)
Biogenic Limestone (Calcium Carbonate, CaCO3)
Amber
Succinite (specifically for Baltic amber; fossilized tree resin)
Quartzite
Quartzite (primarily SiO2)
Serpentine (Serpentinite)
Mg3Si2O5(OH)4
Rough Dark Green Sapphire
Corundum (Al2O3)
Bismuth Crystal
Bismuth (Bi)
Cultured Marble (Synthetic)
Polymer-matrix composite (typically calcium carbonate in polyester resin)
Carnelian Agate
Silicon Dioxide (SiO2) - Chalcedony containing Iron Oxide impurities
Generic Rock / Pebble
Undetermined rock specimen
Unknown Rock Specimen
Apache Tear
Obsidian (Volcanic Glass)
Amber
Fossilized Tree Resin
Gneiss
Metamorphic Gneiss
Chert (with Iron Staining)
Microcrystalline Quartz (SiO2)
River Pebble (Granite/Sandstone Pebble)
Rounded Quartz/Feldspar Gravel Clast
Black Opal Ring (Carved Opal)
Hydrated Silicon Dioxide (SiO2·nH2O)