Glass

Cobalt Blue Glass / Cullet Glass

Silicon dioxide (Amorphous man-made glass)

Polished blue glassy mineral specimen, likely sodalite or blue aventurine

Most consistent with sodalite (Na₈Al₆Si₆O₂₄Cl₂), though dyed quartzite or blue glass cannot be excluded from the photograph

Muscovite Mica

KAl2(AlSi3O10)(F,OH)2

Muscovite Mica

KAl2(AlSi3O10)(OH)2

Chert (Iron-stained)

Microcrystalline Silica (SiO2)

Clear quartz fragment (rock crystal)

Quartz, silicon dioxide (SiO₂)

Blue Cat's Eye

Chatoyant Quartz or Fiber-optic Glass

Cullet Glass (sometimes mistaken for Blue Obsidian or Slag)

Amorphous Silicon Dioxide (SiO2) with chemical additives (e.g., Cobalt for blue color)

Green sea glass (likely)

Anthropogenic glass, not a mineral; composition commonly soda–lime silicate glass

Obsidian

Volcanic Glass (Silica-rich glass)

Opalite

Synthetic glass / Opaque silicious glass

Muscovite Mica

Muscovite (KAl2(AlSi3O10)(OH)2)

Muscovite Mica

Muscovite (KAl2(AlSi3O10)(OH)2)

Muscovite Mica

Muscovite: KAl2(AlSi3O10)(OH)2

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Green glassy mineral specimen, likely chromium-bearing fluorite (tentative)

Fluorite, CaF₂, possibly green fluorite; identification uncertain from image

Cullet (Slag Glass)

Amorphous Silica (Industrial byproduct)

Goldstone

Aventurine glass

Tumbled amber-brown quartz (probable smoky quartz or carnelian)

Quartz, SiO₂; color may reflect iron impurities or irradiation

Tumbled mahogany obsidian

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

Muscovite Mica

Muscovite (KAl2(AlSi3O10)(F,OH)2)

Sea Glass (White/Clear)

Amorphous Silica (Alkali-Lime-Silica Glass), SiO2 + Na2O + CaO

Blue Goldstone

Man-made glass with crystalline copper/cobalt inclusions

Blue slag glass or dyed glass-like industrial material

Amorphous silicate glass; likely copper-bearing blue slag, but possibly colored man-made glass

Green sea glass (likely bottle glass)

Man-made soda-lime silicate glass; not a natural mineral

Sea Glass

Amorphous Silica (Glass) SiO2

Borosilicate Glass (Manufactured)

SiO2 + B2O3 (Silicon dioxide and Boron trioxide)

Goldstone

Aventurine glass (Synthetic glass with copper inclusions)

Opalite

Synthetic Opalite (Man-made glass)

Opalite (a synthetic glass)

Silicon Dioxide (SiO2) with various additives; not a true mineral but a man-made gem simulant

Slag Glass (Cullet Glass)

Amorphous Silica (Industrial byproduct)

Dyed or synthetic turquoise-blue glass-like specimen

Likely man-made colored glass or resin; exact identification requires testing

Green sea glass (likely bottle glass)

Human-processed soda–lime silicate glass; not a natural mineral or rock

Libyan Desert Glass

Impact-melt silica glass (SiO2 + traces of Al, Fe, Ti)

Muscovite Mica

KAl2(AlSi3O10)(OH)2

Quartz with Mica (Pegmatite)

Silicon Dioxide (SiO2) with Potassium Aluminum Silicate Hydroxide (KAl2(AlSi3O10)(OH,F)2)

Snowflake Obsidian

Hydrated Volcanic Glass with Cristobalite inclusions

Quartz with Muscovite Mica

Silicon Dioxide (SiO2) with Potassium Aluminum Silicate Hydroxide (KAl2(AlSi3O10)(OH)2)

Muscovite Mica (with Schist)

Muscovite - KAl2(AlSi3O10)(OH)2

Muscovite Mica

Muscovite - KAl2(AlSi3O10)(OH)2

Goldstone (Brown)

Aventurine Glass (Silicon Dioxide infused with Copper crystals)

Opalite

Synthetic Opalised Glass