Igneous Rock (Volcanic Glass)

Almandine Garnet & Tumbled Citrine Quartz

Fe3Al2(SiO4)3 (Garnet) and SiO2 (Quartz)

Mica Schist (with Golden/Biotite inclusions)

K(Mg,Fe)3AlSi3O10(F,OH)2 (Biotite), KAl2(AlSi3O10)(F,OH)2 (Muscovite)

Amethyst

Silicon Dioxide (SiO2) with iron impurities

Quartz (Milky or Clear Quartz fragment)

Silicon Dioxide (SiO2)

Amethyst

Silicon Dioxide (SiO2) with iron impurities

Jasper and Yellow Chert (Tumbled)

Microcrystalline Quartz (SiO2)

Iron-Stained Quartz (Riverside Cobble)

Silicon Dioxide (SiO2) with Limonite/Hematite inclusions

Green Druzy Quartz (Prasiolite)

Silicon Dioxide (SiO2) with inclusions (typically Chlorite or Actinolite)

Black Obsidian

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

Obsidian

Volcanic Glass (SiO2, usually >70% silica content)

Amethyst

Silicon Dioxide (SiO2) with trace Iron impurities

Agate (or Banded Agate)

Agate (a variety of Chalcedony, which is a cryptocrystalline form of Quartz); Chemical Formula: SiO₂ (Silicon Dioxide)

Granite Pebble

Granite (Phaneritic intrusive igneous rock)

Quartz Pebble (Citrine-colored or Stained Quartz)

Silicon Dioxide (SiO2)

Black Onyx

Onyx (Silicon Dioxide, SiO2)

Quartz (likely Clear Quartz or Rock Crystal)

Quartz (SiO2)

Jasper

Jasper (Silicon Dioxide, SiO2)

Amethyst Quartz

Amethyst (SiO2 with Iron impurities)

Quartz Pebble

Silicon Dioxide (SiO2)

Red Jasper

Silicon Dioxide (SiO2) with iron oxide inclusions

Quartz Geode

Silicon Dioxide (SiO2)

Quartz Crystal (specifically Rock Crystal)

Silicon Dioxide (SiO2)

Amethyst

Amethyst (Silicon Dioxide with Iron impurities, SiO2)

Quartz with Pyrite

Silicon Dioxide (SiO2) with Iron Sulfide (FeS2)

Granite (Granitic Pegmatite/Porphyry)

Felsic intrusive igneous rock (Quartz, Feldspar, Mica composition)

Amethyst

Quartz (SiO2) with trace iron impurities

Raw Diamond (Rough Uncut)

Diamond (C - pure carbon)

Clear Quartz Crystal

Silicon Dioxide (SiO2)

Milky Quartz

Quartz (Silicon Dioxide - SiO2)

Sunstone

Plagioclase Feldspar (specifically Oligoclase variety containing hematite or goethite inclusions)", composition: (Ca,Na)(Al,Si)2Si2O8

Mahogany Obsidian Arrowhead

Volcanic Glass with Hematite/Magnetite inclusions (Amorphous Silicon Dioxide)

Chalcedony (Agate/Chert)

Silicon Dioxide (SiO₂)

Rose Quartz

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

Tree Agate

Dendritic Agate (Silicon Dioxide, SiO2)

Blue Lace Agate

Silicon dioxide (SiO2) - Chalcedony variety

Muscovite on Quartz (Mica host rock)

KAl2(AlSi3O10)(OH)2 (Muscovite) in SiO2 (Quartz)

Quartz (Druzy Quartz)

Silicon Dioxide (SiO2)

Obsidian (specifically Silver Sheen Obsidian)

Volcanic Glass (approx. 70–75% SiO2 plus MgO, Fe3O4)

Jasper (Iron-stained Chalcedony)

SiO2 with Fe2O3 (Iron Oxide) impurities

Quartz Pebble

Silicon Dioxide (SiO2)

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Tree Agate

Dendritic Agate (Silicon Dioxide, SiO2)