Mineral Health

Opal

Hydrated silica (SiO2·nH2O)

Chalcedony (Common Opal or Agate)

Silicon Dioxide (SiO2)

Opal

Hydrated Amorphous Silica (SiO2·nH2O)

Amethyst

Crystalline Quartz (SiO2) with iron impurities

Botryoidal Chalcedony

Silicon Dioxide (SiO2)

Herkimer Diamond (Quartz)

Silicon Dioxide (SiO2)

Sandstone

Arenite (primarily SiO2)

Gold Nugget

Native Gold (Au)

Desert Rose

Gypsum (variety Selenite) or Barite, CaSO4·2H2O

Tiger's Eye

Pseudomorph of Quartz after Crocidolite (SiO2)

Quartz (Smoky Quartz variant)

Silicon Dioxide (SiO2)

Amethyst

Quartz (Silicon Dioxide with iron impurities), SiO2

Orange Quartz (Citrine Quartz)

Silicon Dioxide (SiO2) with iron impurities

Zoisite with Ruby / Anyolite

Anyolite (Ca2Al3(SiO4)3(OH) with Chromian Zoisite and Tschermakite inclusions)

Amethyst (Quartz variety)

Silicon Dioxide (SiO2) with iron impurities

Chalcedony with Druzy Quartz Geode

Silicon Dioxide (SiO2)

N/A - Image is non-geological

Acrylonitrile Butadiene Styrene (ABS) or Polypropylene (PP)

Quartzite and Jasper Pebbles

Quartzite (re-crystallized Quartz) and Cryptocrystalline Quartz (SiO2)

Chalcedony Geode Fragment (Botryoidal)

Silicon Dioxide (SiO2) - Cryptocrystalline Quartz

Kyanite

Kyanite (Al2SiO5)

Red Sandstone

Arenite (Ferruginous Sandstone)

Garden Quartz (Phantom Quartz)

Silicon Dioxide (SiO2) with various inclusions (often Chlorite, Hematite, or Iron)

Red Sandstone

Arenite with Iron Oxide (Hematite) cement

Red Sandstone

Arenite (with Iron Oxide / Hematite staining)

Jasper containing epidote (Unakite-like)

Epidotized Jasper (SiO2 with Ca2(Al,Fe)3(SiO4)3(OH))

Sandstone (Ferruginous)

Arenite with Iron-Oxide Cement (primarily SiO2 with Fe2O3/FeOOH)

Turquoise

CuAl6(PO4)4(OH)8·4H2O (Hydrated copper and aluminum phosphate)

Lepidolite

K(Li,Al)3(Al,Si)4O10(F,OH)2 (Lithium-bearing phyllosilicate)

Basalt with Quartz/Zeolite Inclusions

Porphyritic Basalt (SiO2 with Aluminosilicates)

Malachite

Copper Carbonate Hydroxide [Cu2CO3(OH)2]

Red Sandstone Pebble

Arenite with Hematite (Fe2O3) cement

Red Sandstone

Arenite (with Iron Oxide pigmentation)

Chatoyant Quartz (Cat's Eye Quartz)

Silicon Dioxide (SiO2) with fibrous inclusions of Amphibole or Rutile

Basalt with Quartz/Calcite Veins

Aphanitic Mafic Igneous Rock (Hydrothermal Veined)

Milky Quartz with Iron Inclusions

Crystalline Silicon Dioxide (SiO2)

Granite Pegmatite

Phaneritic Felsic Igneous Rock (Granite)

Granite

Granite (Phaneritic Igneous Rock)

Granodiorite / Granite (Weathered)

Granodiorite

Chipped Glass/Plastic Fragment

Silicon dioxide (SiO2) for glass (amorphous) or various polymer compounds for plastic

Breciated Jasper

Silicon Dioxide (SiO2) with iron oxide inclusions

Quartz (Iron-stained)

Silicon Dioxide (SiO2)

Quartz with Iron Staining

Crystalline Silicon Dioxide (SiO2)