Black Obsidian
Volcanic Glass (SiO2 with impurities)
Category
Browse mineral and glass specimens identified by the Rock Identifier community.
Black Obsidian
Volcanic Glass (SiO2 with impurities)
Quartz Crystal
Silicon Dioxide (SiO2)
Milky Quartz
Silicon Dioxide (SiO2)
Quartz pebble with iron inclusions
Silicon Dioxide (SiO2)
Quartz Pebble
Silicon Dioxide (SiO2)
Sandstone (Ferruginous)
Arenite with Iron-Oxide Cement (primarily SiO2 with Fe2O3/FeOOH)
Milky Quartz
Quartz (Silica / Silicon Dioxide), SiO2
Obsidian
Volcanic Glass (Primary composition: SiO2 - Silicon Dioxide)
Pyrite in Quartz
Silicon Dioxide (SiO2) with Iron Sulfide (FeS2)
Pyrite in Quartz Matrix
Iron Disulfide (FeS2) in Silicon Dioxide (SiO2)
Pyrite (Iron Pyrites)
Iron Sulfide (FeS2)
Quartzite Pebble
Quartzite (primarily Silicon Dioxide, SiO2)
Pegmatite
Coarse-grained Igneous Rock (Granitic Pegmatite)
Chalcedony Agate / Carnelian nodules in Matrix
SiO2 (Silicon Dioxide) with iron oxide inclusions
Quartz (Microcrystalline/Macro crystalline variety)
Silicon Dioxide (SiO2)
Milky Quartz
Silicon Dioxide (SiO2)
Quartz (River Pebble)
Silicon Dioxide (SiO2)
Mixed Quartz and Jasper Pebbles
Silicon Dioxide (SiO2)
Milky Quartz Pebble
Silicon Dioxide (SiO2)
Milky Quartz
Silicon Dioxide (SiO2)
Milky Quartz
Silicon Dioxide (SiO2)
Quartz (Granular)
Silicon Dioxide (SiO2)
Smoky Quartz
Quartz (Silicon Dioxide, SiO2)
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
Citrine Quartz (Raw)
Silicon Dioxide (SiO2)
Rose Quartz
Silicon Dioxide (SiO2)
Amethyst (Agate/Chalcedony variety)
Silicon Dioxide (SiO2) with iron impurities
Milky Quartz
Silicon Dioxide (SiO2)
Quartz (Milky or Smoky Quartz)
Quartz (Silicon Dioxide, SiO2)
Hematoid Quartz
Ferruginous Quartz (SiO2 with Fe2O3 inclusions)
Yellow Quartz (Citrine or Iron-Stained Quartz)
Silicon Dioxide (SiO2)
Milky Quartz with Iron Staining
Silicon Dioxide (SiO2)
Banded Slag Glass (Leland Blue/Frankfort Green style)
Anthropogenic Glass Specimen (Amorphous Silicon Dioxide with impurities)
Clear Quartz (faceted) / Diamond Simulant
Silicon Dioxide (SiO2) / Cubic Zirconia (ZrO2)
Quartz (Iron-stained)
Silicon Dioxide (SiO2)
Obsidian
Volcanic Glass (70% or more SiO2)
Quartz (Milky or Cloudy)
Silicon Dioxide (SiO2)
Green Jasper / Green Quartz
Silicon dioxide (SiO2) with mineral impurities
Banded Jasper
Silicate Mineral (Microcrystalline Quartz / SiO2)
Milky Quartz
Quartz (SiO2)
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
Milky Quartz
Quartz (Silicon Dioxide, SiO2)