Man Made Glass Mineral Simulant

Sandstone (Ferruginous)

Arenite (Fe2O3 stained)

Green Fluorite

Calcium Fluoride (CaF2)

Quartz (Citrine or Iron-Stained variety)

Silicon Dioxide (SiO2)

Green Aventurine

Aventurine Quartz (SiO2 with Fuchsite inclusions)

Green Aventurine

SiO2 (Silicon Dioxide) with Fuchsite inclusions

Green Aventurine (Double-Terminated Wand)

Silicon Dioxide (SiO2) containing Fuchsite (Chromium-rich Muscovite Mica)

Possible weathered quartz-rich rock or iron-stained mineral fragment

Indeterminate; possibly quartz (SiO₂) with iron-oxide inclusions

Quartz

Silicon Dioxide (SiO2)

Quartz pebble

SiO2

Chert Nodules in Limestone

Microcrystalline Quartz (SiO2) in Carbonate Matrix

Quartzite with Iron Inclusions

Quartzite (primarily SiO2 with Fe2O3 impurities)

Jasper with Iron Oxides

Silicon Dioxide (SiO2) with Fe2O3 inclusions

Tumbled milky quartz (probable)

Quartz, silicon dioxide (SiO₂)

Amethyst

Silicon Dioxide (SiO2) with iron impurities

Quartz Geode with Calcite

Silicon Dioxide (SiO2) with Calcium Carbonate (CaCO3)

Chert / Chalcedony

Silicon Dioxide (SiO2)

Weathered quartz-rich rock, possibly milky quartz or quartz-bearing granite

Quartz (SiO₂), potentially with feldspar and iron-oxide staining

Multi-Gemstone Quartz Bracelet (Amethyst, Aventurine, Rose Quartz, Clear Quartz)

Silicon Dioxide (SiO2) mixture

Weathered quartz-rich pebble

Milky quartz, chiefly silicon dioxide (SiO₂), possibly with iron-oxide staining and minor feldspar

Milky Quartz (with trace inclusions)

Silicon Dioxide (SiO2)

Fluorite (Rainbow/Purple Fluorite)

Calcium Fluoride (CaF2)

Pink Sapphire (Corundum)

Aluminum Oxide (Al2O3) with Chromium/Iron impurities

Tumbled yellow chalcedony (likely citrine or yellow jasper)

Microcrystalline quartz, SiO₂; exact identification is uncertain from the photograph

Tumbled cream chalcedony or quartz

Microcrystalline quartz, SiO₂; possibly iron-stained chalcedony

Yellow chalcedony (likely lemon quartz or citrine)

Cryptocrystalline silica, SiO₂; possible quartz variety

Milky Quartz / Quartz Geode Fragment

Silicon Dioxide (SiO2)

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Clear Quartz

Quartz (Silicon Dioxide, SiO2)

Agate (Plume/Moss variety)

Cryptocrystalline Quartz (SiO2) with iron/manganese inclusions

Citrine

Citrine (Silicon Dioxide - SiO2)

Quartz (Milky Quartz / Greenish Quartz)

SiO2 (Silicon Dioxide)

Smoky Quartz

Smoky Quartz (Silicon Dioxide - SiO2)

Pyrite

Iron Sulfide (FeS2)

Milky Quartz

Silicon Dioxide (SiO2)

Quartz cluster, possibly druzy quartz on matrix

Quartz (SiO₂), likely microcrystalline to coarse crystalline; associated matrix uncertain

Fluorite

Calcium Fluoride (CaF2)

Muscovite (Mica)

Muscovite - KAl2(AlSi3O10)(OH)2

Muscovite Mica

Muscovite - KAl2(AlSi3O10)(OH)2

Libyan Desert Glass

Libyan Desert Glass (Impactite / High-silica Lechatelierite)

Clear Quartz

Silicon Dioxide (SiO2)

Quartz-rich translucent pebble, possibly iron-stained quartz or chalcedony

Quartz (SiO₂), potentially microcrystalline quartz (chalcedony)

Iron-stained Quartz Pebble

Silicon Dioxide (SiO2) with Hematite/Limonite coatings