Man Made Mineral Simulant (Glass)

Mahogany Obsidian

Volcanic glass (high silica) with inclusions of Magnetite or Hematite

Purple Fluorite Octahedron

Fluorite (Calcium Fluoride, CaF2)

Obsidian

Obsidian (Volcanic Glass, ~70% SiO2)

Obsidian

Volcanic glass (SiO2-rich)

Green fluorite (likely)

Fluorite — calcium fluoride, CaF₂

Raw Citrine Quartz

Silicon Dioxide (SiO2)

Muscovite

Muscovite (KAl2(AlSi3O10)(OH)2)

Green Fluorite

Fluorite (Calcium Fluoride, CaF2)

Slag Glass (Cullet Glass)

Amorphous Silica (Industrial byproduct)

Blue Calcite

Calcite (Calcium Carbonate, CaCO3)

Weathered quartz-rich cobble, possibly quartzite or feldspar-rich granite

Quartz–feldspar aggregate; identification is uncertain from the photograph

Obsidian

Obsidian (Volcanic Glass)

Quartz Pebble

Silicon Dioxide (SiO2)

Rough Apatite in Matrix

Fluorapatite / Chlorapatite / Hydroxylapatite (Ca5(PO4)3(F,Cl,OH))

Obsidian (black volcanic glass)

Obsidian; predominantly rhyolitic volcanic glass, mainly SiO₂ with minor feldspar, quartz, and iron oxides

Milky quartz fragment

Quartz (silicon dioxide, SiO₂)

Snowflake Obsidian

Volcanic glass with Phenocrysts (SiO2)

Obsidian

Volcanic Glass (Amorphous Silica, SiO2)

Black Obsidian

Obsidian (Volcanic Glass), primarily SiO2 (Silicon Dioxide)

Milky Quartz Pebble

Silicon Dioxide (SiO2)

Quartz Nut

SiO2 (Silicon Dioxide)

Polished orbicular jasper (likely ocean jasper)

Silicified microcrystalline quartz/chalcedony with iron-oxide-rich orbicules; commonly called Ocean Jasper

Mica / Muscovite or Biotite

Phyllosilicate mineral group (e.g., KAl2(AlSi3O10)(OH)2)

Tumbled Quartz Pebble

Silicon Dioxide (SiO2)

Chert (Flint)

Microcrystalline Quartz (SiO2)

Fluorite

Calcium Fluoride (CaF2)

Quartz

Silicon Dioxide (SiO2)

Quartz

Silicon Dioxide (SiO2)

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Snowflake Obsidian

Volcanic glass containing Cristobalite (SiO2)

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Slag Glass

Silicon dioxide with impurities

Blue-green raw mineral specimen, likely apatite

Fluorapatite, Ca₅(PO₄)₃F (probable; visual identification only)

Quartz Vein Rock

Silicon dioxide (SiO2) within a host rock matrix

Clear quartz crystal point

Quartz (silicon dioxide, SiO₂), likely a polished or cut crystal

Fulgurite

Fulgurite (Lechatelierite-rich variety)

Pink Granite (Unakite-bearing or Epidote-bearing Granite)

Plutonic Igneous Rock (Granite)

Garden Quartz (Lodalite)

Silicon Dioxide with various mineral inclusions (SiO2)

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Clear Quartz

Silicon dioxide (SiO2)

Clear Quartz

SiO2 (Silicon Dioxide)

Chert (or possibly Flint)

Chert (variant: Flint)