Obsidian
Volcanic glass (SiO2 - Silicon Dioxide with impurities)
Category
Browse man made glass specimens identified by the Rock Identifier community.
Obsidian
Volcanic glass (SiO2 - Silicon Dioxide with impurities)
Vesicular Basalt (Lava Rock)
Vesicular Basalt (comprising plagioclase feldspar and pyroxene group minerals)
Quartz
Quartz (SiO₂)
Coral Rock (Coquina)
Biogenic Limestone (Calcium Carbonate - CaCO3)
Quartz (Milky Quartz)
Silicon Dioxide (SiO2)
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
Milky Quartz
Silicon Dioxide (SiO2)
Granite
Granite (a common rock type, not a single mineral with a formula. Composed primarily of quartz, feldspar, and mica/amphibole).
Obsidian
Obsidian (Volcanic Glass)
Yellow Quartz
Silicon Dioxide (SiO2)
Garnet Beads
Garnet Group (complex nesosilicates, e.g., Almandine Fe3Al2(SiO4)3)
Limestone
Calcium Carbonate (CaCO3)
Quartz (Iron-stained)
Silicon Dioxide (SiO2)
Milky Quartz
Silicon Dioxide (SiO2)
Quartz (Rock Crystal) with minor impurities
Quartz (SiO2)
Quartzite
Quartzite (chiefly SiO2)
BROWN GRANITE (likely 'Tan Brown' or similar)
Granite (specifically a variety rich in orthoclase feldspar, often with biotite and possibly hornblende)
Milky Quartz
Silicon Dioxide (SiO2)
Orange Quartz
Silicon Dioxide (SiO2) with iron inclusions
Milky Quartz
Silicon Dioxide (SiO2)
Chert (or potentially massive Quartz/Quartzite)
SiO2 (Silicon Dioxide)
Rhodonite
Rhodonite (MnSiO3)
Quartzite
Quartzite (primarily SiO2)
Costume Jewelry Gemstones (Emerald-imitation and semi-precious beads)
BeCuAl6Si6O18 (Beryl structure), frequently simulated by glass or synthetic spinel
Quartzite
Quartzite (SiO2)
Limestone
Sedimentary Rock (Calcium Carbonate, CaCO3)
Granite
Granite
Multi-Gemstone Quartz Bracelet (Amethyst, Aventurine, Rose Quartz, Clear Quartz)
Silicon Dioxide (SiO2) mixture
Quartz Grain
Silicon Dioxide (SiO2)
Quartz Geode Fragment
Silicon Dioxide (SiO2)
Milky Quartz
Silicon Dioxide (SiO2)
Limestone (River Pebble)
Calcium Carbonate (CaCO3)
Diamond (or Diamond Simulant)
Carbon (C) if diamond, various if simulant (e.g., Cubic Zirconia - ZrO2, Moissanite - SiC)
Milky Quartz
Silicon Dioxide (SiO2)
Quartzite with Iron Inclusions
Quartzite (primarily SiO2 with Fe2O3 impurities)
Greasy Quartz (likely carved Milky Quartz or Aventurine)
Silicon Dioxide (SiO2)
Quartz
Quartz (SiO₂)
Milky Quartz
Silicon Dioxide (SiO2)
Sandstone
Arenite (composed primarily of SiO2)
Strawberry Quartz (Hematoid Quartz)
Silicon Dioxide with Iron Oxide inclusions (SiO2 + Fe2O3)
Quartzite
Quartzite (predominantly SiO2)