Obsidian
Volcanic Glass (Primary composition: SiO2 - Silicon Dioxide)
Category
Browse anthropogenic (man made artifact) specimens identified by the Rock Identifier community.
Obsidian
Volcanic Glass (Primary composition: SiO2 - Silicon Dioxide)
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
Clear Quartz
Silicon Dioxide (SiO2)
Red Jasper
Silicon Dioxide (SiO2)
Citrine
Silicon Dioxide (SiO2) with iron impurities
Unakite
Epidotized Granite
Quartz (Milky/Gold-stained)
Silicon Dioxide (SiO2)
Milky Quartz
Silicon Dioxide (SiO2)
Quartzite
Metamorphosed Quartz Sandstone (SiO2)
Apache Tear
Obsidian (Hydrated Silica / Amorphous Volcanic Glass)
Sandstone (Ferruginous)
Arenite (primarily SiO2 with Fe2O3/FeO(OH) cementing agents)
Agate (Bead Form)
Agate (Cryptocrystalline Quartz, SiO2)
Carnelian (Red Chalcedony)
Silicon Dioxide (SiO2)
Tufa (Vesicular Limestone)
Tufa (form of Calcium Carbonate, CaCO3)
Nephrite Jade
Nephrite (Ca2(Mg, Fe)5Si8O22(OH)2)
Emerald
Beryl (Be3Al2Si6O18 with Chromium/Vanadium impurities)
Chrysoprase
Chrysoprase (a variety of Chalcedony, SiO₂)
Orthoclase Feldspar
KAlSi3O8 (Potassium Aluminum Silicate)
Banded Gneiss (River Rock/Pebble)
Gneiss (specifically a banded variety often found as a river rock)
Rhodonite
Rhodonite; (Mn,Fe,Mg,Ca)SiO3
Rhodonite
Rhodonite (MnSiO3)
White Quartz Pebble
Silicon Dioxide (SiO2)
Milky Quartz
Quartz (Silicon Dioxide - SiO2)
Milky Quartz Pebble
Silicon Dioxide (SiO2)
Quartzite (River Stone)
Quartzite (SiO2)
Milky Quartz
Silicon Dioxide (SiO2)
Green Chert (Jasper)
Silicon Dioxide (SiO2)
Quartz
Silicon Dioxide (SiO2)
Basalt (River Rock Cobble)
Extrusive mafic volcanic rock (Basalt)
Basalt (River Pebble)
Extrusive mafic igneous rock
Quartzite
Quartzite (Primary mineral: SiO2)
Quartz Pebble (Chalcedony/Agate)
Silicon Dioxide (SiO2)
Banded Iron Formation (BIF) / Tiger Iron variety
Banded Iron Formation (composed primarily of Magnetite Fe3O4, Hematite Fe2O3, and Chert/Quartz SiO2)
Amethyst (Geode)
Silicon Dioxide (SiO2) with iron impurities
Amethyst
Silicon Dioxide (SiO2) with iron impurities
Citrine Quartz
Silicon Dioxide (SiO2) with iron impurities
Clear Quartz
Silicon dioxide (SiO2)
Chert (specifically Red Chert or Jasper)
Microcrystalline Quartz (SiO2)
Gneiss
Gneiss (High-grade metamorphic rock)
Milky Quartz
Silicon Dioxide (SiO2)
Milky Quartz
Silicon Dioxide (SiO2)
Jade (likely Jadeite)
Jadeite (a pyroxene mineral) or Nephrite (a variety of amphibole mineral)