Mineral Like (Natural Glass)

Blue Slag Glass

Ferro-silicate glass (Slag)

Jasper-bearing Quartzite River Cobble

Tectonized Quartzite with Iron-Oxide (Hematite/Limonite) Veining

Snowflake Obsidian

Volcanic Glass (SiO2 with Cristobalite inclusions)

Sandstone

Arenite

Blue-dyed tumbled quartz or glass imitation

Quartz (SiO₂), appearance possibly enhanced with blue dye; identity uncertain from image

Sandstone (Quartzose)

Arenite (composed primarily of SiO2)

Sandstone (with minor quartz and possible clay components)

Clastic Sedimentary Rock (SiO2 dominated)

Sandstone (Quartzose)

Arenite (composed primarily of SiO2)

Quartz (Rose Quartz / Quartz Pebble)

Silicon Dioxide (SiO2)

Opalite

Synthetic glass / Opalized glass

Smoky Quartz

Quartz (Silicon Dioxide), Formula: SiO2

Sandstone

Arenite (primarily Quartz, SiO2)

Clear Quartz (Tumbled)

Silicon Dioxide (SiO2)

Diamond (or diamond simulant)

C

Aventurine Quartz

Silicon Dioxide (SiO2) with Fuchsite inclusions

Dyed Quartz Geode

Silicon Dioxide (SiO2) with artificial pigment

Smoky Quartz

Silicon Dioxide (SiO2)

Tumbled pale-yellow quartz (likely citrine or iron-stained quartz)

Quartz, silicon dioxide (SiO₂); yellow color likely from iron-related impurities

Sandstone (likely Arkose or Quartz Sandstone)

Clastic sedimentary rock (primarily SiO2)

Yellow Topaz (Imperial/Golden Topaz)

Topaz - Al2SiO4(F,OH)2

Blue Topaz

Al2SiO4(F,OH)2

Sandstone

Arenite (SiO2 primarily)

Smoky Quartz

Silicon Dioxide (SiO2) with aluminum impurities

Green Slag Glass

Cullet (Amorphous Silicon Dioxide with impurities)

Tumbled carnelian (orange chalcedony)

Carnelian, a microcrystalline variety of quartz (SiO₂), commonly colored by iron oxides

Smoky Quartz

Smoky Quartz (Silicon Dioxide - SiO2)

Green Quartz (likely Aventurine or Prasiolite)

Silicon Dioxide (SiO2) with inclusions

Sandstone (Quartzose Sandstone)

Arenite

Sandstone (Calcareous Sandstone)

Calcareous Sandstone (primarily SiO2 with CaCO3 cement)

Corundum (Ruby Variety)

Corundum (Al2O3)

Banded Slag Glass (Leland Blue/Frankfort Green style)

Anthropogenic Glass Specimen (Amorphous Silicon Dioxide with impurities)

Sandstone (Beach Pebble)

Clastic sedimentary rock (primarily Quartz and Feldspar)

Slag (Industrial Byproduct)

Ferrous/Non-ferrous Silicate

Smoky Quartz

Silicon Dioxide (SiO2)

Amethyst (with Pyrite and other minerals)

Silicon Dioxide (SiO2)

Yellow Quartz (Citrine or Iron-Stained Quartz)

Silicon Dioxide (SiO2)

Yellow Quartz

Silicon Dioxide (SiO2)

Clear quartz crystal (likely)

Quartz, silicon dioxide (SiO₂)

Smoky Quartz

Silicon Dioxide (SiO2) with aluminum impurities

Smoky Quartz

Silicon Dioxide (SiO2)

Sandstone (Quartz-rich)

Arenite (composed mainly of SiO2)

Tumbled yellow quartz (likely citrine or iron-stained quartz)

Quartz, SiO₂; yellow color from trace iron or irradiation/heat-related coloration