Mineral Precipitate (Anthropogenic Context)

Pyrite (Fool's Gold)

Iron Sulfide (FeS2)

Pyrite

Iron Sulfide (FeS2)

Phantom Quartz (Chlorite Inclusion)

Silicon Dioxide (SiO2) with Chlorite (Mg,Fe,Al)6(Si,Al)4O10(OH)8

Green Common Opal

Hydrated Silica (SiO2·nH2O)

Peridot

Olivine (Mg,Fe)2SiO4

Chrysocolla

Chrysocolla (Cu2-xAlx(H2-xSi2O5)(OH)4·n H2O)

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

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

Jasper containing epidote (Unakite-like)

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

Turquoise

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

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

Chatoyant Quartz (Cat's Eye Quartz)

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

Banded Calcite or Travertine

Calcium Carbonate (CaCO3)

Basalt with Iron Oxides

Mafic Igneous Rock (Mafite)

Glauconitic Sandstone

Glauconitic Quartz Sandstone (K(Fe,Al)2(Si,Al)4O10(OH)2)

Diorite

Intermediate Phaneritic Igneous Rock

Lepidolite

K(Li,Al)3(Al,Si,Rb)4O10(F,OH)2

Tiger's Eye

Pseudomorph of Crocidolite (SiO2 with iron oxides)

Sodalite

Sodalite (Na8Al6Si6O24Cl2)

Native Copper (in coinage alloy)

Copper (Cu)

Rhodochrosite

Manganese carbonate (MnCO3)

Granite

Granite (Phaneritic Igneous Rock)

Granodiorite / Granite (Weathered)

Granodiorite

Sodalite

Na8(Al6Si6O24)Cl2

Chondrite Meteorite

Ordinary Chondrite (S-type Asteroid fragment)

Granite Pegmatite

Phaneritic Felsic Igneous Rock (Granite)

Sandstone

Arenite (SiO2 principal)

Sandstone

Arenite (composed primarily of SiO2)

Sandstone (Quartz Arenite)

Sandstone (Chemical formula: primarily SiO2)

Sandstone (Quartzose)

Arenite (composed primarily of SiO2)

Lepidolite (likely)

K(Li,Al)3(Al,Si)4O10(F,OH)2 (Phyllosilicate mineral, part of the mica group)

Amygdaloidal Basalt

Amygdaloidal Basalt (Mafic silicate with secondary mineral inclusions)

Quartzite with Dark Mineral Inclusions

Quartzite (primarily SiO2) with accessory minerals

Chipped Glass/Plastic Fragment

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

Sandstone

Arenite (primarily SiO2)

Veined Pebble (likely a Quartz-Veined Pebble)

Pebble with Mineral Vein (e.g., Quartz Vein in a Chert/Mudstone Pebble)