Mahogany Obsidian
Volcanic Glass (predominantly SiO2 with Fe2O3 inclusions)
Category
Browse none specimens identified by the Rock Identifier community.
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
Metamorphic Rock (Mainly SiO2)
Tumbled Obsidian
Volcanic Glass (Silicon Dioxide)
Quartzite River Rock
Quartzite (primarily SiO2)
Quartzite
Quartzite (primarily SiO2)
Black Obsidian
Volcanic Glass (Primary composition: SiO2 - Silicon Dioxide)
Quartzite
Quartzite (primarily SiO2)
Obsidian
Volcanic glass (no mineral formula due to amorphous structure, mostly SiO2)
Zebra Rock (Zebra Stone / Ribbon Stone)
Siltstone with Ferruginous Banding (Primarily Quartz, Kaolinite, and Hematite)
Black Obsidian
Obsidian (Volcanic Glass), primarily SiO2 (Silicon Dioxide) with impurities
Quartzite
Quartzite (composed primarily of Quartz, SiO2)
Quartzite (Water-Worn)
Quartzite (SiO2)
Ethiopian Opal (Welo Opal in Matrix)
Hydrated Silica (SiO2·nH2O)
Red Quartzite (Tumbled Pebble)
Quartzite (primarily SiO2 with hematite inclusions)
Tektite (Indochinite)
Tektite (Amorphous Meteoritic Glass)
Quartzite (Yellow/Tan)
Metamorphic Rock composed of Quartz (SiO₂)
Quartzite
Quartzite (primarily SiO2)
Tektite
Tektite (Amorphous silica rich glass)
Mahogany Obsidian
Volcanic Glass (Silicate: SiO2 + Fe2O3)
Quartzite
Quartzite (primarily SiO2)
Obsidian
Obsidian (principally SiO2)
Amber
Succinite (fossilized tree resin)
Amber
Succinite (a fossilized organic resin containing succinic acid)
Chert (variously identified as Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Amber
Succinite (fossilized resin); C10H16O
Snowflake Obsidian
Vitreous volcanic silicate rock (SiO2) with Spherulite inclusions
Anthracite Coal
Low-grade metamorphic carbonaceous rock
Obsidian
Volcanic Glass (70-75% SiO2)
Obsidian
Volcanic Glass (Primary component: SiO2)
Amber
Succinite (a Fossilized Tree Resin); Chemical formula is approximately C10H16O
Obsidian
Obsidian (Volcanic Glass, SiO2 + impurities)
Limestone (specifically fossiliferous/skeletal limestone)
Calcium Carbonate (CaCO3)
Apache Tear (Obsidian)
Obsidian (Hydrated Amorphous Silica, SiO2 + MgO/Fe3O4)
Obsidian
Volcanic Glass (SiO2)
Obsidian
Obsidian (Volcanic Glass, SiO2 + impurity)
Mahogany Obsidian
Volcanic Glass (SiO2 + Fe2O3)
Obsidian
Volcanic glass (high silica content based on SiO2)
Obsidian
Volcanic Glass (SiO2)
Amber
Succinite (Fossilized Resin C10H16O)