Mineral Simulant (Synthetic Glass)

Quartz Vein in Hematitic Siltstone

Hydrothermal Quartz (SiO2) in Ferriferous Matrix

Slag Glass

Vitreous Silicate Residue

Obsidian

Volcanic glass

Polished white agate or chalcedony bead

Microcrystalline quartz (SiO₂), likely chalcedony/agate with iron-oxide staining or a brown mineral inclusion

Quartz Pebble

Silicon Dioxide (SiO2)

Green fluorite (likely)

Fluorite — calcium fluoride, CaF₂

Quartz with Feldspar Veining

Silica (SiO2) with Potassium Feldspar (KAlSi3O8) inclusions

Quartz (specifically Clear and Rose Quartz)

Silicon Dioxide (SiO2)

Obsidian

Obsidian (Volcanic Glass)

Smoky quartz

Quartz (SiO₂), naturally irradiated brown variety

Quartz Pebble

Quartz (Silicon Dioxide, SiO2)

Sandstone with Iron Staining

Arenite (SiO2 with Fe2O3)

Polished black stone, likely black obsidian

Obsidian (volcanic glass; mainly SiO₂)

Quartz (Iron-stained)

Silicon Dioxide (SiO2)

Milky Quartz

Quartz (Silica - SiO2)

Epidote

Epidote (Ca2(Al2,Fe3+)(SiO4)(Si2O7)O(OH))

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

Milky Quartz / Quartz Geode Fragment

Silicon Dioxide (SiO2)

Agate (Plume/Moss variety)

Cryptocrystalline Quartz (SiO2) with iron/manganese inclusions

Clear/White Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Iron-stained Quartz Pebble

Silicon Dioxide (SiO2) with Hematite/Limonite coatings

Quartz (Iron-stained)

Silicon Dioxide (SiO2) with Iron Oxide inclusions

Lodolite (Garden Quartz)

Silicon Dioxide (SiO2) with inclusions (Chlorite, Hematite, etc.)

Rose Quartz

Silicon dioxide (SiO2) with trace amounts of titanium, iron, or manganese

Quartz Pebble (Iron-Stained)

Silicon Dioxide (SiO2)

Snowflake Obsidian

Spherulitic Volcanic Glass (SiO2)

Sandstone

Arenite

Quartz Crystal Matrix

Silicon Dioxide (SiO2)

Quartz Pebble

Silicon Dioxide (SiO2)

Chert with Calcite Veins

Silicon Dioxide (SiO2) with Calcium Carbonate (CaCO3) intrusions

Quartz Pebble

Quartz (Silicon Dioxide, SiO2)

Quartz River Pebble

Silicon Dioxide (SiO2)

Rose Quartz

Silicon Dioxide (SiO2)

Quartz

Silicon Dioxide (SiO2)

Hand-Drawn Trading Card (Amateur Artwork)

Cellulose-based substrate with wax/graphite/ink deposit (n/a for minerals)

Iron-stained Quartz

Silicon Dioxide with Limonite (SiO2 + FeO(OH)·nH2O)

Quartz

Silicon Dioxide (SiO2)

Quartz

Silicon Dioxide (SiO2)

Quartz in Matrix

Silicon Dioxide (SiO2)

Weathered quartz-rich cobble, possibly milky quartz with iron staining

Quartz (SiO₂), likely with iron-oxide/hydroxide coatings and minor host-rock inclusions

Obsidian

Volcanic Glass (SiO2)