Tektite (Natural Glass)

Beaded gemstone jewelry (likely amethyst, lapis lazuli, and pearl or glass imitation)

Mixed mineral beads; possible quartz (SiO₂) and lazurite-bearing lapis lazuli

Diamond (or diamond simulant)

C

Carnelian and Strawberry Quartz

Silicon Dioxide (SiO2) with Hematite and Limonite inclusions

Clear Quartz

Silicon Dioxide (SiO2)

Chert (Holey Stone)

Microcrystalline Quartz (SiO2)

Aventurine Quartz

Silicon Dioxide (SiO2) with Fuchsite inclusions

Libyan Desert Glass

Libyan Desert Glass (Impactite / High-silica Lechatelierite)

Sandstone

Clastic sedimentary rock (Quartz arenite)

Sandstone

Sedimentary Rock (Quartz arenite / Lithic sandstone)

Possible industrial slag or basaltic volcanic glass

Likely iron-rich vitreous slag; natural alternative: basaltic glass (tachylite)

Pink-red faceted gemstone, possibly synthetic corundum or spinel

Uncertain; possible ruby (corundum, Al₂O₃) or red spinel (MgAl₂O₄)

Quartzite

Quartzite (SiO2)

Sandstone

Arenite

Green Aventurine

Silicon Dioxide (SiO2) with inclusions of Fuchsite

Green aventurine (likely)

Quartz variety; silicon dioxide (SiO₂), commonly colored by fuchsite mica or other inclusions

Citrine

Silicon Dioxide (SiO2)

Sea Glass

Amorphous silicon dioxide (man-made glass weathered by nature)

Clear faceted gemstone in a gold-colored setting

Likely colorless quartz (rock crystal) or synthetic cubic zirconia; visual identification is inconclusive

Green glassy slag or manufactured glass bead

Noncrystalline silicate glass; likely industrial glass/slag, not a true mineral

Black tourmaline (schorl), possibly rough obsidian

Schorl tourmaline: NaFe₃Al₆(BO₃)₃Si₆O₁₈(OH)₄; visual confirmation is limited

Terrazzo flooring containing marble aggregate

Marble (recrystallized calcite, CaCO₃) aggregate in cementitious terrazzo

Blue Goldstone

Goldstone (artificial glass)

Likely tumbled yellow-orange mineral or glassy stone

Indeterminate from photograph; possibilities include yellow jasper, calcite, agate, or dyed quartz

Likely quartz cabochon in a ring

Quartz (SiO₂), possibly clear or milky quartz; identification is uncertain from the photograph

Citrine

Silicon Dioxide (SiO₂)

Tumbled amber-colored mineral or glassy pebble

Uncertain; likely chalcedony/quartz, possibly resinous amber or slag glass

Blue Chalcedony (likely dyed Agate)

Silicon Dioxide (SiO₂)

Blue glass-like heart pendant, likely synthetic blue spinel or colored glass

Unconfirmed; possibly synthetic spinel (MgAl₂O₄) or cobalt-colored glass

Smoky Quartz

Silicon Dioxide (SiO2)

Blue Cat's Eye Quartz (Heated/Dyed)

Silicon Dioxide (SiO2) with fibrous inclusions

Blue glass-like gemstone, likely synthetic spinel or glass

Uncertain; possibilities include synthetic cobalt-blue spinel (MgAl₂O₄) or cobalt-colored glass

Green sea glass (likely bottle glass)

Man-made soda–lime silicate glass; not a natural mineral

Yellow Quartz (Citrine Quartz or Yellow Chalcedony)

Silicon Dioxide (SiO2)

Sandstone

Arenite (SiO2 based)

Sandstone

Arenite (primarily Quartz Arenite)

Milky Quartz Pebble

Silicon Dioxide (SiO2)

Small gray translucent stone, possibly quartz or glassy mineral

Uncertain; likely microcrystalline quartz (SiO₂), but the image is insufficient for definitive identification

Sandstone

Sandstone (clastic sedimentary rock)

Sandstone

Arenite (SiO2 based)

Sandstone (Ferruginous)

Arenite (Fe2O3 stained)

Goldstone

Aventurine glass (Synthetic glass with copper inclusions)

Milky quartz pebble

Quartz (silicon dioxide, SiO₂)