Man Made Object (Ring)

Diamond (or high-quality simulant like Cubic Zirconia)

Carbon (C) - Native Element

Opal

Hydrated Silica (SiO2·nH2O)

Bloodstone (Heliotrope)

Silicon Dioxide (SiO2) - Variety of Chalcedony/Jasper

Pearl

Calcium Carbonate (Aragonite and Calcite), CaCO3

Pearl

Calcium carbonate (CaCO3) in the form of Aragonite or Calcite

Peach Moonstone

Orthoclase Feldspar (KAlSi3O8) with inclusions

Dragon Blood Jasper

Epidote-containing Quartz and Chlorite (SiO2 + (Ca2(Al, Fe)3(SiO4)3(OH)))

Moonstone

Orthoclase Feldspar ((K,Na)AlSi3O8)

Pearl

Aragonite (CaCO3) with Conchiolin

Tahitian Black Pearl

Biogenic Calcium Carbonate (Aragonite/Conchiolin Mixture), CaCO3

Morganite (Pink Beryl)

Beryllium aluminum silicate Be3Al2(SiO3)6

Black Onyx

Chalcedony (SiO2) with parallel banding

Pearl

Calcium Carbonate (Aragonite/Calcite mixed with Conchiolin), CaCO3

Peach Moonstone

Orthoclase (Potassium Aluminum Silicate), KAlSi3O8

Amethyst Geode

Amethyst (Silicon Dioxide), Formula: SiO2

Amethyst with Marcasite accents

Amethyst (Silicon Dioxide SiO2) and Marcasite (Iron Sulfide FeS2)

Peridot (Olivine)

Magnesium Iron Silicate (Mg,Fe)2SiO4

Diamond (or Cubic Zirconia)

Crystallized Carbon (C) for Diamond; Zirconium Dioxide (ZrO2) for CZ

Amethyst

SiO2 (Silicon Dioxide with iron impurities)

Clear Quartz (Herkimer Diamond variant)

Silicon Dioxide (SiO2)

Rough Citrine Quartz

Citrine (Silicon Dioxide, SiO2 with iron impurities)

Smoky Quartz

Smoky Quartz (Silicon Dioxide - SiO2)

Fuchsite in Quartz (Aventurine Quartz)

K(Al,Cr)2(AlSi3O10)(OH)2 (Fuchsite) + SiO2 (Quartz)

Carnelian Agate

Silicon Dioxide (SiO2) with iron oxide impurities

Sandstone (Picture Sandstone)

Arenite (primarily SiO2 with iron oxide impurities)

Carnelian

Carnelian (a variety of Chalcedony); SiO2 (Silicon Dioxide)

Wonderstone (Sandstone)

Liesegang Banded Sandstone (SiO2 dominated)

Sandstone (Ferruginous)

Arenite (Fe-bearing Clastic Sedimentary Rock)

Wonderstone

Banded Rhyolite (SiO2 with impurities)

Carnelian

Chalcedony (Silicon Dioxide / SiO2)

Carnelian

Carnelian (SiO2 - Silicon Dioxide)

Carnelian

Chalcedony (Silicon Dioxide, SiO2)

Carnelian (Red-Orange Chalcedony)

Silicon Dioxide (SiO2)

Carnelian (a variety of Chalcedony)

SiO2 (Silicon Dioxide) primarily colored by iron oxide (Hematite)

Turquoise

Hydrated phosphate of copper and aluminium [CuAl6(PO4)4(OH)8·4H2O]

Larimar

Pectolite (a variety of pectolite, NaCa2Si3O8(OH))

Sandstone (with Iron Staining)

Clastic sedimentary rock (primarily SiO2)

Anthracite Coal

Anthracite (high-rank coal)

Rose Quartz

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

Amber

Fossilized tree resin (not a true mineral as it is organic and amorphous); Chemical formula is highly variable, but often approximated as C10H16O.

Green Aventurine

Quartz (Aventurine variety) - SiO₂ with Fuchsite inclusions

Amazonite

Amazonite (KAlSi3O8 – a variety of Microcline, a Potassium Feldspar)