Tektite (Natural Glass)

Quartz (likely heat-treated or colored cord)

Silicon Dioxide (SiO2)

Opalite

Man-made synthetic glass with opalescent effects (SiO2 + metal oxides)

Yellow Quartz or Citrine

Silicon Dioxide (SiO2)

Citrine

Citrine (Silicon Dioxide - SiO2)

Chrysocolla and Malachite Beads

Hydrated copper silicates (Chrysocolla) and Copper carbonate hydroxide (Malachite)

Ferruginous Quartz

Silicon Dioxide (SiO2) with Iron Oxide inclusions

Faceted clear gemstone (likely glass imitation or quartz)

Uncertain; appearance is consistent with colorless quartz (SiO₂), but the strong uniform brilliance may indicate cut glass or cubic zirconia

Tumbled smoky quartz

Quartz, silicon dioxide (SiO₂), smoky variety

Pearl and Garnet Glass

Calcium Carbonate (CaCO3) for pearl; Silicon Dioxide (SiO2) for glass

Pink faceted gemstone, likely synthetic or treated quartz

Quartz, silicon dioxide (SiO₂); exact identity cannot be confirmed from the image

Purple quartz fragments, likely amethyst

Amethyst (quartz, SiO₂)

Sandstone

Arenite (primarily SiO2)

Sandstone (likely Quartzose)

Arenite (primarily SiO2)

Sandstone

Arenite

Opalite

Synthetic Opalised Glass

Green glassy gemstone-like specimen

Likely synthetic glass or treated quartz; exact identification requires testing

Rhinestone (or glass crystal)

Silicon dioxide (if glass) / Various

Goldstone

Aventurine Glass (Man-made)

Smoky Quartz

Smoky Quartz (Silicon Dioxide, SiO2)

Pumice

Pumice (Felsic vesicular volcanic glass)

Green Aventurine

Aventurine Quartz (SiO2 + Fuchsite mica)

Smoky Quartz

Silicon Dioxide (SiO2)

Chert (Jasper)

Silicon Dioxide (SiO2)

Red Jasper with Quartz

Silicon Dioxide (SiO2) with Hematite impurities

Red Jasper (Chert)

Silicon Dioxide (SiO2) with iron oxide inclusions

Chert (specifically Yellow Jasper variety)

Silicon Dioxide (SiO2)

Chert (Banded)

Cryptocrystalline Silica (SiO2)

Yellow Quartz Pebble

Silicon Dioxide (SiO2)

Quartzite

Quartzite (SiO2)

Fulgurite (Sand-tube)

Fulgurite (Lechatelierite-rich fused sand)

Red carnelian (polished chalcedony)

Carnelian, microcrystalline quartz (SiO₂), cryptocrystalline variety of chalcedony

Likely citrine or yellow quartz fragment

Quartz, SiO₂; possibly iron-colored citrine

Green Aventurine

Aventurine Quartz (SiO2 with Fuchsite inclusions)

Green Aventurine

Silicon Dioxide (Quartz with Fuchsite inclusions) - SiO2 + K(Al,Cr)2(AlSi3O10)(OH)2

Polished mahogany obsidian

Volcanic glass (mostly SiO₂), commonly called mahogany obsidian

Polished black stone, possibly obsidian

Volcanic glass (obsidian), chiefly amorphous SiO₂

Blue glassy mineral fragment, possibly sodalite or dyed/cobalt glass

Uncertain; likely sodalite (Na₈Al₆Si₆O₂₄Cl₂) if natural, but vivid blue color may indicate cobalt-colored glass

Mahogany obsidian crystal point

Volcanic glass, primarily rhyolitic silica (SiO₂), with iron-oxide inclusions

Green Aventurine

Quartzite (Silicon Dioxide, SiO2 + Fuchsite)

Green Aventurine

Silicon Dioxide (SiO2) with inclusions of Fuchsite

Green Aventurine

Silicon Dioxide (SiO2) with Fuchsite inclusions

Aventurine

SiO2 (Silicon Dioxide with Fuchsite inclusions)