Tektite (Natural Glass)

Sandstone

Arenite (primarily SiO2)

Diamond (or Diamond Simulant)

Carbon (C) if diamond, various if simulant (e.g., Cubic Zirconia ZrO2)

Faceted colorless gemstone, likely quartz or glass imitation

Most likely quartz (SiO₂), though the strong glare and visible facet pattern could indicate cubic zirconia or lead glass

Opalite

Synthetic glass (SiO2 + metal additions)

Green Quartz (Prasiolite)

Crystalline Silicon Dioxide (SiO2) with iron impurities

Blue glassy gemstone-like specimen

Indeterminate; possibly dyed or treated turquoise, blue apatite, or man-made glass

Polished jasper/chalcedony nodule

Microcrystalline quartz (SiO₂), likely jaspery chalcedony with iron-oxide staining

Green Aventurine

Quartz containing Fuchsite (SiO2 + K(Al,Cr)2AlSi3O10(OH)2)

Opalite

Man-made Glass (Synthetic Opalized Glass)

Slag Glass / Industrial Slag

Anthropogenic Glass

Sandstone

Arenite

Sandstone (River Cobble)

Clastic sedimentary rock (primarily SiO2)

Sandstone

Arenite (SiO2 based)

Faceted colorless gemstone, likely quartz (rock crystal) or synthetic glass imitation

Quartz: silicon dioxide (SiO₂), trigonal crystal system; exact identity cannot be confirmed visually

Apache Tear

Hydrated Obsidian (Natural Volcanic Glass)

Clear faceted gemstone, likely quartz (rock crystal)

Quartz, silicon dioxide (SiO₂); visual identification is uncertain because the stone is heavily faceted and photographed with flash

Blue Aura Quartz

Silicon Dioxide (SiO2) with metallic vapor coating

Citrine

Citrine (Silicon Dioxide, SiO2)

Citrine Quartz

Silicon Dioxide (SiO2)

Opalite

Synthetic Glass (Simulated Opal)

Yellow Quartz (Rough)

Silicon Dioxide (SiO2)

Decorative opal-like turtle mosaic

Likely imitation or assembled opal material; exact stones cannot be confirmed visually

Polished black gemstone, likely obsidian

Volcanic glass; primarily silica-rich rhyolitic composition (approximately SiO₂)

Green Quartz (Prasiolite)

Crystalline Silicon Dioxide (SiO2)

Blue-dyed tumbled quartz or glass imitation

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

Sandstone

Arenite (SiO2 based)

Sandstone

Arenite (Silicon Dioxide, SiO2 based)

Tumbled Yellow Quartz (Golden Quartz / Citrine)

Silicon Dioxide (SiO2)

Blue Slag Glass

Amorphous Silica (Industrial byproduct)

Diamond

Natural Diamond (Carbon, C)

Amethyst (likely tumbled or cut fragment)

Quartz, silicon dioxide (SiO₂), purple variety colored mainly by iron impurities and irradiation

Faceted Clear Quartz or Diamond Simulant

Silicon Dioxide (SiO2) if Quartz or Cubic Zirconia (ZrO2) if Synthetic

Citrine Quartz (likely heat-treated)

Silicon Dioxide (SiO2)

Quartz (Iron-stained)

Silicon Dioxide (SiO2)

Faceted yellow-brown gemstone ring, likely citrine

Citrine (iron-bearing quartz, SiO₂); identification from the photo is uncertain

Polished star-shaped gemstone, likely black obsidian

Obsidian (volcanic glass), predominantly SiO₂

Pumice

Vesicular volcanic rock, primarily silica-rich volcanic glass (commonly rhyolitic or dacitic)

Strawberry Quartz and Rose Quartz

Silicon Dioxide (SiO2) with inclusions

Clear quartz crystal (likely quartz bead/specimen)

Quartz, silicon dioxide (SiO₂)

Dyed Blue Agate Slice

Chalcedony (Silicon Dioxide, SiO2)

Amethyst (Water-Worn Pebble)

Silicon Dioxide (SiO2 with iron impurities)

Rough Citrine Quartz

Silicon Dioxide (SiO2) with ferric iron impurities