Mineral, Possibly Rock Fragment Containing A Mineral

Chert (containing Iron Oxide)

Microcrystalline Quartz (SiO2)

Gneiss

Gneiss (High-grade Regional Metamorphic Rock)

Diamond

Carbon (C)

Granite

Granite (Felsic intrusive igneous rock)

Granite Pebble

Granite (Phaneritic intrusive igneous rock)

Giallo Ornamental Granite

Phaneritic Igneous Rock (composed of Quartz, Feldspar, and Mica)

Granite

Phaneritic Felsic Igneous Rock

Jasper

Silicon dioxide (SiO2)

Ocean Jasper

Silicon dioxide with impurities (SiO2 + impurities)

Dalmatian Stone

Dalmatian Stone (a peralkaline igneous rock consisting of Feldspar, Quartz, and Arfvedsonite)

Agate (Carnelian / Chalcedony)

Silicon Dioxide (SiO2)

Red Jasper

Jasper (Silicon Dioxide with Iron Oxide inclusions), SiO2 + Fe2O3

Rose Quartz

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

Quartz

Silicon Dioxide (SiO2)

Quartz (Iron-stained)

Silicon Dioxide (SiO2)

Quartz Geode

Silicon Dioxide (SiO2)

Calcite Geode

Calcium Carbonate (CaCO3)

Yellow Ochre / Limonite

Hydrated Iron(III) Oxide-Hydroxide (FeO(OH)·nH2O)

Manganese-coated Sandstone

Clastic sedimentary rock with Manganese Oxide (often Pyrolusite or Psilomelane)

Amethyst (Tumbled)

Amethyst (Silicon Dioxide, SiO2 + Fe4+)

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Clear Quartz Point

Silicon Dioxide (SiO2)

Milky Quartz

Silicon Dioxide (SiO2)

Clear Quartz Sphere

Quartz (Silicon Dioxide, SiO2)

Quartz

Silicon dioxide (SiO2)

Clear Quartz

Silicon Dioxide (SiO2)

Almandine Garnet in Matrix

Almandine (Fe3Al2(SiO4)3)

Orthoclase Feldspar (Salmon variety)

Orthoclase, KAlSi3O8

Diabase (Dolerite) Cobble

Diabase / Dolerite

Granite

Granite (Felsic Plutonic Rock)

Granite

Granite (Felsic Plutonic Rock)

Granodiorite

Granodiorite

Granite with Orthoclase and Hematite Staining

Phaneritic Felsic Igneous Rock (primarily SiO2 with KAlSi3O8)

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Slag

Metallurgical by-product

Ferruginous Sandstone

Arenite with Iron-Oxide Cement (FeO(OH)·nH2O / Fe2O3)

Granite

Granite (a felsic intrusive igneous rock)

Granite

Granite (a common rock type, not a single mineral with a formula. Composed primarily of quartz, feldspar, and mica/amphibole).

Milky Quartz

Quartz (Silicon Dioxide - SiO2)

Hematite

Iron(III) oxide (Fe2O3)

Diorite (Polished River Pebble)

Diorite (Intermediate intrusive igneous rock)