Tektite (Natural Glass)

Mixed rounded rock and mineral gravel

Predominantly weathered basalt, quartz-rich fragments, and iron-stained silicate rocks; exact species cannot be determined reliably from the image

Faceted glass-like gemstone (likely synthetic quartz or cubic zirconia)

Identification uncertain; possibilities include synthetic quartz (SiO₂) or cubic zirconia (ZrO₂)

Citrine Quartz

Silicon Dioxide (SiO2)

Opalite

Synthetic Glass (typically Silica/Magnesium based with metal additives)

Green chalcedony (likely chrysoprase or dyed chalcedony)

Microcrystalline quartz, SiO₂; chrysoprase is nickel-bearing chalcedony

Chert (Jasper)

Microcrystalline Quartz (SiO2)

Banded Chert

Silicon Dioxide (SiO2) with impurities

Chalcedony (River Pebble)

Silicon Dioxide (SiO2)

Citrine (Heat-treated or Natural Quartz)

Silicon Dioxide (SiO2)

Quartzite

Quartzite (SiO2)

Citrine Quartz (or Heat-Treated Amethyst / Smoky Quartz)

Silicon Dioxide (SiO2)

Amethyst

Silicon Dioxide (SiO2 with iron impurities)

Colorless faceted gemstone, likely synthetic cubic zirconia

Cubic zirconia (zirconium dioxide, ZrO₂); natural diamond is a less likely alternative

Cabochon gemstone ring, likely smoky quartz or tourmaline

Unconfirmed quartz (SiO₂) or brown tourmaline (dravite); visual identification is inconclusive

Jasper and Agate Beads (Mahogany Obsidian, Dyed Agate, Turquoise/African Turquoise)

Silicon Dioxide (SiO2) mixture with inclusions / Hydrated Copper Aluminum Phosphate

Quartz pebble

Silicon dioxide (SiO2)

Citrine (likely Heat-Treated Amethyst)

Silicon Dioxide (SiO2)

Sandstone

Sedimentary Rock (Quartz arenite)

Sandstone

Quartzose Sandstone (Sedimentary Rock)

Polished black stone, likely black obsidian

Obsidian (volcanic glass; predominantly SiO₂)

Red faceted gemstone, likely synthetic ruby or red spinel

Ruby: corundum (Al₂O₃); spinel: MgAl₂O₄; visual identification alone is insufficient

Mahogany Obsidian

Volcanic Glass with Hematite or Magnetite (SiO2 + Fe2O3)

Smoky quartz (likely)

Quartz, silicon dioxide (SiO₂), naturally irradiated variety

Tumbled white quartz pebble

Quartz (silicon dioxide, SiO₂), likely milky quartz

Faceted transparent gemstone pendant

Uncertain from image; likely faceted quartz (SiO₂), cubic zirconia (ZrO₂), or glass imitation

Blue Topaz

Aluminum silicate fluoride hydroxide (Al2SiO4(F,OH)2)

Rose Quartz Beads

Crystalline Silicon Dioxide (SiO2) with trace amounts of titanium, iron, or manganese

Quartz (Double-Terminated)

Silicon Dioxide (SiO2)

Amethyst

Silicon Dioxide (SiO2) with iron impurities

Smoky Quartz

Silicon Dioxide (SiO2)

Quartz with Epidote

Silicon Dioxide (SiO2) with Calcium Aluminum Iron Silicate [Ca2(Al,Fe)3(SiO4)3(OH)]

Flint / Chert

Silicon Dioxide (SiO2)

Strawberry Quartz (or Rose Quartz / Cherry Quartz)

Silicon Dioxide (SiO2) with Lepidocrocite, Hematite, or Goethite inclusions

Dyed tumbled quartz (likely quartzite or quartz crystal)

Quartz, silicon dioxide (SiO₂)

Citrine

Silicon dioxide (SiO2)

Tumbled yellow-orange chalcedony (likely carnelian or jasper)

Microcrystalline quartz, SiO₂; iron-oxide coloration

Banded agate cabochon

Agate, a microcrystalline variety of chalcedony (SiO₂), likely carnelian/white-banded agate

Quartz (Milky Quartz / Clear Quartz)

Silicon Dioxide (SiO2)

Red Jasper with Quartz Veining

Jasper (Silicon Dioxide, SiO2)

Citrine

Silicon Dioxide (SiO2) with ferric iron impurities

Quartz Pebble

Silicon Dioxide (SiO2)

Smoky quartz (likely citrine-colored quartz) ring

Quartz, SiO₂; precise variety cannot be confirmed from the photograph