Synthetic Glass (Man Made)

Clear quartz crystal

Quartz (silicon dioxide, SiO₂)

Tumbled white chalcedony (likely milky quartz)

Chalcedony, microcrystalline quartz (SiO₂)

Tumbled milky quartz (likely)

Quartz, silicon dioxide (SiO₂)

Milky quartz (likely rough quartz crystal)

Quartz, silicon dioxide (SiO₂)

Not a rock, mineral, or geological specimen

Green Aventurine

Silicon Dioxide (SiO2) with inclusions of Fuchsite (K(Al,Cr)2AlSi3O10(OH)2)

Blue opalite glass cabochon (likely imitation opal)

Man-made opalescent glass; not a natural mineral

Man-made Green Quartz (Lab-grown or Treated)

Silicon Dioxide (SiO2) with artificial coloration

Green iridescent glass cabochon or synthetic gemstone

Likely synthetic glass; possibly coated synthetic quartz or lab-created green gemstone

Glass

Amorphous Silicon Dioxide (SiO2)

Faceted gemstone in a jewelry setting

Indeterminate from image; likely quartz, cubic zirconia, or another transparent faceted stone

Sea Glass (specifically Frosted White)

Amorphous Silica (substance: Sodium-calcium silicate glass)

Cobalt Glass Slug (Cullet)

Man-made Silicate Glass with Cobalt Oxide (CoO)

Diamond (or Diamond Simulant)

Carbon (C) or Cubic Zirconia (ZrO2)

Blue Goldstone

Aventurine Glass

Green Aventurine

SiO2 (Silicon Dioxide with Fuchsite inclusions)

Small pebble, likely limestone

Unidentified carbonate pebble, possibly micritic limestone (calcite, CaCO₃)

Polished milky quartz (likely quartz worry stone or wand)

Quartz, silicon dioxide (SiO₂)

White quartz pebble

Quartz (SiO₂), likely milky quartz

Polished black pebble, likely basalt

Basalt, a fine-grained mafic volcanic rock composed mainly of plagioclase feldspar and pyroxene, commonly with olivine

Aventurine Quartz

Silicon Dioxide (SiO2) with Fuchsite inclusions

Small rounded mineral pebble, possibly quartz

Uncertain; likely microcrystalline or crystalline SiO₂ (quartz), potentially with iron-oxide staining

Green glass-like mineral specimen, likely fluorite

Fluorite (calcium fluoride, CaF₂), if natural; appearance may also indicate colored glass

Aura Quartz (Titanium/Rainbow Quartz)

SiO2 (Silicon Dioxide) with metallic coating

Slag Glass

SiO2 (Silicon Dioxide) with impurities

Likely tumbled or cut quartz/chalcedony fragment

Silicon dioxide (SiO₂), probably microcrystalline quartz or quartz

Concrete Fragment

Artificial Conglomerate (Cement and Aggregate)

Goldstone (Brown/Gold)

Aventurine Glass (Man-made glass with Copper inclusions)

Goldstone

Aventurine Glass (Man-made glass with copper inclusions)

Tumbled quartz pebble

Quartz, silicon dioxide (SiO₂), likely milky quartz

Diamond (or Simulant)

Carbon (C)

Goldstone (Synthetic Aventurescence Glass)

Cuprous Aventurescent Glass (Silicon Dioxide with Copper inclusions)

Milky quartz (rough quartz fragment)

Quartz, silicon dioxide (SiO₂)

Cullet Glass (Slag Glass)

Amorphous Silicon Dioxide (Industrial byproduct)

Silicon Carbide (Carborundum)

Silicon Carbide (SiC) / Moissanite (natural)

Opalite (likely imitation opal glass)

Man-made opalescent glass; not a natural mineral (often sold as opalite)

Polished black stone, likely black obsidian

Volcanic glass; predominantly rhyolitic silica glass (SiO₂-rich)

Slag

Anthropogenic glassy silicate

White quartz pebble or chip

Quartz (silicon dioxide, SiO₂), possibly milky quartz

Unidentified translucent crystal/mineral fragment

Likely quartz (SiO₂), but visual identification is uncertain

Green Aventurine

Silicon Dioxide (Quartz with Fuchsite inclusions), SiO2

Clear quartz crystal (likely)

Quartz, silicon dioxide (SiO₂)