Mineral (Specifically A Gemstone Variety)

Serpentine

Antigorite, Lizardite, or Chrysotile (Mg, Fe)3Si2O5(OH)4

Cloudy Quartz (or Milky Quartz)

Silicon Dioxide (SiO2)

Red Granite

Phaneritic Felsic Intrusive Igneous Rock (primarily K-feldspar, Quartz, and Biotite)

Chert (Flint)

Silicon Dioxide (SiO2)

Pink Granite

Phaneritic Felsic Intrusive Igneous Rock (composed of Quartz, Alkali Feldspar, and Plagioclase)

Chert (Iron-stained)

Microcrystalline or cryptocrystalline Quartz (SiO2)

Yellow Jasper

Silicon Dioxide (SiO2) with iron oxide impurities

Chert (often called Flint)

Chert (Cryptocrystalline Quartz, SiO2)

Chert (Iron-stained)

Microcrystalline Quartz (SiO2)

Pink Granite

Phaneritic Felsic Igneous Rock (Granite)

Agate (specifically Botswana or Lake Superior style Agate)

Silicon Dioxide (SiO2) - Microcrystalline Quartz

Agate (specifically a Yellow/Honey Agate)

Silicon Dioxide (SiO2) - Microcrystalline Quartz

Chalcedony (specifically Common Opal or Agate variant)

Silicon Dioxide (SiO2)

Fluorite (specifically Rainbow Fluorite or Purple Fluorite)

Calcium Fluoride (CaF2)

Agate (specifically, a slice of a Blue Lace or Chalcedony Agate nodule)

Silicon Dioxide (SiO2) - Cryptocrystalline Quartz

Aragonite (specifically Mexican Marbled Onyx)

Aragonite (Calcium Carbonate, CaCO3)

Banded Agate (specifically Sardonyx or Carnelian Agate)

Silicon Dioxide (SiO2) - Cryptocrystalline Quartz

Red Jasper

SiO2 (Silicon Dioxide with Iron inclusions)

Basalt

Basalt (Mafic volcanic rock)

Sandstone (River Cobble)

Arenite

Selenite (Satin Spar)

Gypsum (CaSO4·2H2O)

Orthoceras Fossil Limestone

Orthoceras (extinct Cephalopod fossil) in Matrix

Amethyst (Pale/Lavender variety)

Silicon Dioxide (SiO2)

Quartz

Silicon Dioxide (SiO2)

Quartz

Silicon Dioxide (SiO₂)

Gneiss (specifically Banded Gneiss)

Gneiss

Chert (Yellow Jasper)

Microcrystalline Quartz (SiO2)

Jasper

Silicon Dioxide (SiO2)

Botryoidal Chalcedony

Chalcedony (SiO2)

Peridot (Olivine)

Olivine, (Mg,Fe)2SiO4

Gneiss (specifically Micaceous Gneiss)

Gneiss (High-grade Regional Metamorphic Rock)

Sandstone (specifically Arkose or Quartz Arenite)

Arenite (primarily SiO2 with possible Feldspar)

Quartz (Rose or Milky variety fragment)

Silicon Dioxide (SiO2)

Rose Quartz

Silicon Dioxide (SiO2) with trace impurities of Titanium, Manganese, or Iron

Garnet Schist

Garnet-bearing Mica Schist (variety of compositions, often Al2SiO5 with X3Y2(SiO4)3)

Chert (Flint variety)

Chert (Cryptocrystalline Quartz, SiO2)

Jasper

Silicon Dioxide (SiO2) with iron oxide impurities

Green Aventurine

Silicon Dioxide (SiO2) with Fuchsite inclusions (Quartzite)

Citrine Quartz

Citrine (Silicon Dioxide - SiO2)

Unakite

Epidotized Granite

Blue Chalcedony

Silicon Dioxide (SiO2)

Gneiss (specifically Pink Gneiss)

Gneiss (high-grade regional metamorphic rock)