Synthetic Material (Not A Rock Or Mineral)

Diamond (in a jewelry setting)

Cubic Carbon (C)

Diamond (set in a gold ring)

Carbon (C) - Adamantine cubic carbon

Quartz Geode Fragment

Silicon Dioxide (SiO2)

Amber

Succinite (fossilized resin, C10H16O)

Quartz with Muscovite Mica

Silicon Dioxide (SiO2) with Potassium Aluminum Silicate Hydroxide Fluoride (KAl2(AlSi3O10)(F,OH)2)

Jasper

Silicon Dioxide (SiO2)

Herkimer Diamond

Quartz (Silica - SiO2)

Granite

Plutonic felsic rock (Quartz, Feldspar, Mica)

Banded Slate or Siltstone with Quartz/Calcite Veins

Protolith-derived Siltstone or Slate (varies based on degree of metamorphism)

Concrete with Aggregate

Composite construction material; primary matrix is Calcium Silicate Hydrate (C-S-H)

Chert (Nodule)

Microcrystalline Quartz (SiO2)

Tektite (likely Australite)

Tektite (no specific chemical formula as it's a natural glass of variable composition, mostly SiO2, Al2O3, FeO, MgO, CaO, K2O, Na2O, TiO2)

Basalt with Peridotite Inclusion

Mafic Volcanic Rock (Extrusive Igneous) with Ultramafic Xenolith

Rough Diamond

Pure Carbon (C)

Diamond (or Diamond Simulant/Cubic Zirconia)

Carbon (C) - if diamond, or Zirconium dioxide (ZrO2) - if Cubic Zirconia

Quartz (specifically Clear and Rose Quartz)

Silicon Dioxide (SiO2)

Quartz

Quartz (SiO₂)

Amethyst Geode (Thunderegg)

Silicon Dioxide (SiO2) - Quartz Variety: Amethyst

Gold Nugget

Native Gold (Au)

Moss Agate

Chalcedony (SiO2) with inclusions of manganese or iron oxides

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Sandstone or Quartzite

Arenite (if sedimentary) / Quartzite (if metamorphic)

Limonite

Limonite (Hydrated iron(III) oxide-hydroxide) FeO(OH)·nH2O

Jasper (Iron-stained Chert)

Silicon Dioxide (SiO2) with iron oxide inclusions

Sandstone

Arenite

Chert (with Limestone/Dolomite host)

Microcrystalline Quartz (SiO2)

Banded Gneiss

Gneiss (high-grade metamorphic silicate rock)

Quartz (Druzy on Matrix)

Silicon Dioxide (SiO2)

Green Jasper (with Quartz veining)

Jasper (Silica-rich microcrystalline variety of Quartz), formula: SiO2

Quartzite

Quartzite (primarily SiO2)

Quartz Geode

Silicon Dioxide (SiO2) within a geode

Quartz

Silicon Dioxide (SiO2)

Banded Calcite (Mexican Onyx)

Calcium Carbonate (CaCO3)

Petrified Wood

Silicified Wood (SiO2)

Quartz-veined Mudstone or Argillite

SiO2 (Quartz) in Siltstone/Mudstone matrix

Onyx (Black) and Mother of Pearl Inlay

Silicon Dioxide (SiO2) for Onyx; Aragonite (CaCO3) for Mother of Pearl

Quartzite Pebble

Quartzite (SiO2)

Sandstone with Concretions / Liesegang Rings

Arenite with iron oxide banding

Banded Sandstone

Arenite (with iron oxide banding)

Quartz (likely Jasper or Chert variety)

Quartz (SiO₂)

Orange Quartzite / Quartz

Silicon Dioxide (SiO2) with iron oxide inclusions

Sandstone

Quartz Arenite (a type of sandstone composed of more than 90% quartz)