Manufactured Glass (Simulant)

Chert (Flint variety)

Silicon Dioxide (SiO2)

Black obsidian (possibly industrial glass or slag)

Volcanic glass; predominantly rhyolitic composition, chiefly SiO₂

Green Slag Glass

Cullet (Amorphous Silicon Dioxide with impurities)

Slag Glass

Silicon dioxide with impurities

Unidentified small mineral fragment

Possibly quartz or feldspar-bearing rock; exact identification is uncertain from the image

Sandstone (Weathered / Crushed)

Quartz Sandstone

Quartz Pebble

Silicon Dioxide (SiO2)

Sea Glass (Uranium/Vaseline Glass variant)

Silicon Dioxide (SiO2) with trace Uranium Oxide (U3O8)

Tumbled black stone, likely obsidian

Obsidian (natural volcanic glass; mainly silica-rich rhyolitic composition)

Clear quartz crystal (likely quartz point/fragment)

Quartz, silicon dioxide (SiO₂)

Obsidian

Volcanic glass (SiO2-rich amorphous silicate)

Weathered sandstone or iron-rich sedimentary rock fragments

Quartz-rich sandstone, locally ferruginous; exact identification requires testing

Mixed gemstone bead bracelet, likely lava rock and aventurine/jade-look beads

Basaltic scoria (vesicular basalt), plus probable serpentine, aventurine, or dyed quartzite beads

Quartz Pebble

Silicon Dioxide (SiO2)

Quartz Pebble

Silicon Dioxide (SiO2)

Sandstone (Quartzose Sandstone)

Clastic Sedimentary Rock (primarily SiO2)

Quartz Pebble

Silicon Dioxide (SiO2)

K-Feldspar (Potassium Feldspar / Pink Feldspar)

KAlSi3O8 (Potassium Aluminum Silicate)

Quartz pebble

Silicon dioxide (SiO2)

Quartz Pebble

Silicon Dioxide (SiO2)

Milky Quartz Pebble

Silicon Dioxide (SiO2)

Possible flint/chert fragment

Microcrystalline quartz (SiO₂), likely chert or flint

Red glassy cabochon, likely synthetic ruby or red glass

Uncertain; possible synthetic corundum (Al₂O₃, chromium-colored) or man-made glass

Tumbled blue glass-like specimen, possibly dyed chalcedony or synthetic glass

Uncertain; possible dyed quartz/chalcedony (SiO₂), but appearance strongly suggests cobalt-blue glass

Quartz (Clear Quartz)

Silicon Dioxide (SiO2)

Quartz (River Pebble)

Silicon Dioxide (SiO2)

Goldstone (Brown/Gold variety)

Aventurine Glass (SiO2 with Copper inclusions)

Obsidian (likely black volcanic glass)

Obsidian; naturally occurring rhyolitic glass, primarily SiO₂

Red jasper (likely polished and carved)

Jasper, an opaque microcrystalline variety of quartz (SiO₂), colored mainly by iron oxides

Opalite

Synthetic Glass (Simulated Opal)

Synthetic Resin Charm (Seal Shape)

Polymer Resin with plastic glitter / Polyethylene terephthalate glitters

Slag Glass (Cullet)

Amorphous Silicon Dioxide (SiO2) with metal oxide colorants

Cullet (Slag Glass)

Amorphous Silica (SiO2) with various metal oxide colorants

Black tumbled stone, possibly obsidian

Undetermined; appearance may resemble obsidian (volcanic glass, SiO₂-rich)

Quartzite

Metamorphic Quartzite (SiO2)

Sandstone

Arenite (SiO2 primarily)

Sandstone

Arenite (SiO2 primarily)

Quartz pebble

Silicon Dioxide (SiO2)

Quartz

Silicon Dioxide (SiO2)

Feldspar in Matrix

Feldspar group minerals in metamorphic or igneous matrix

Quartz Crystal

Silicon Dioxide (SiO2)

Quartz Pebble

Silicon Dioxide (SiO2)