Mineral Like (Natural Glass)

Sandstone (Ferruginous)

Arenite (primarily SiO2 with iron oxide staining/cementing)

Greenish quartz (likely prase/chalcedony)

Quartz, SiO₂; possibly green chalcedony or chlorite-included quartz

Quartz Pebble

Silicon Dioxide (SiO2)

Citrine Quartz Cluster

Silicon Dioxide (SiO2)

Diamond (or Cubic Zirconia simulant)

Carbon (C) or Zirconium Dioxide (ZrO2)

Polished amethyst pyramid

Amethyst, purple quartz (SiO₂)

Sandstone (River Stone)

Arenite (composed primarily of SiO2)

Aquamarine (Tumbled)

Beryl (Be3Al2Si6O18)

Goldstone (with Tiger's Eye and Quartz)

Aventurine glass (Synthetic SiO2 with Cu inclusions)

Rough smoky quartz

Quartz, silicon dioxide (SiO₂), likely iron- or radiation-colored smoky variety

Tumbled amethyst with quartz and likely agate inclusions

Amethyst, purple quartz (SiO₂), with included/mixed quartz; crystalline variety of quartz

Sandstone

Sedimentary Clastic Rock (Quartz Arenite)

Strawberry Quartz

Silicon Dioxide (SiO2) with Hematite/Goethite inclusions

Sandstone (Micaceous)

Arenite (composed primarily of SiO2)

Smoky Quartz

Silicon Dioxide (SiO2)

Yellow Quartz (Citrine or Iron-Stained Quartz)

Silicon Dioxide (SiO2)

Green aventurine quartz (probable)

Quartz, SiO₂, with fuchsite or other green mica inclusions

Green obsidian (likely molded or heat-treated glass-like specimen)

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

Sandstone (Quartzose)

Arenite (composed mainly of SiO2)

Likely amethyst cabochon ring

Quartz, SiO₂; purple coloration from trace iron and irradiation

Sandstone with Iron Staining

Arenite with Limonite/Hematite inclusions (SiO2 + Fe2O3/FeO(OH))

Smoky Quartz

Smoky Quartz (Silicon Dioxide, SiO2)

Sandstone (Ferruginous)

Arenite with Iron-Oxide Cement

Amethyst

Silicon Dioxide (SiO2) with iron impurities

Citrine Quartz

Silicon Dioxide (SiO2)

Opalite

Synthetic Glass (Hydrated Silica Simulant)

Sandstone (Ferruginous)

Sandstone (primarily SiO2 with iron oxide cement Fe2O3)

Sandstone (Quartzose Sandstone)

Arenite (SiO2 principal component)

Clear Quartz

Silicon Dioxide (SiO2)

Clear Quartz

Silicon Dioxide (SiO2)

Sandstone

Arenite (SiO2 primarily)

Sandstone (with potential Quartzite characteristics)

Clastic sedimentary rock (primarily SiO2)

Red aventurine

Silicon Dioxide (SiO2) with Hematite/Goethite inclusions

River Quartz (Milky and Smoky mix)

Silicon Dioxide (SiO2)

Hematite cameo or hematine imitation

Hematite (Fe₂O₃); possibly synthetic hematine or black glass

Rough Corundum (likely Sapphire/Zircon-bearing)

Aluminium Oxide (Al2O3)

Silver Nuggets (Natural or Cast)

Native Silver (Ag)

Tiger’s-eye bracelet/bead segment

Chatoyant quartz (SiO₂), likely brown tiger’s-eye with iron-oxide alteration

Diamond

C (Carbon)

Clear Quartz

Silicon Dioxide (SiO2)

Blue aventurine or dyed blue quartzite pendant

Quartz (SiO₂), likely aventurine quartz/quartzite; exact identification requires testing

Diamond

Carbon (C)