Crystal

Milky Quartz

Silicon Dioxide (SiO2)

Andesite Porphyry

Porphyritic Andesite (Intermediate volcanic rock)

Granite (Background) and Quartzite/River Pebble (Foreground Heart)

Phaneritic Felsic Igneous Rock (Granite background)

Yellow Jasper

Silicon Dioxide (SiO2) with Iron inclusions

Orange Calcite

Calcium Carbonate (CaCO3)

Epidosite (Epidote-rich rock)

Epidotalite (primarily Ca2(Al2Fe3+)(SiO4)(Si2O7)O(OH))

Unakite (Tumbled)

Epidotized Granite

Yellow Quartz (Chalcedony/Agate)

Silicon Dioxide (SiO2)

Blue Calcite

Calcium Carbonate (CaCO3)

Quartz (specifically Citrine or Iron-stained Quartz)

Silicon Dioxide (SiO2)

Epidote

{Ca2}{Al2Fe3+}(Si2O7)(SiO4)O(OH)

Strawberry Quartz (Lepidocrosite/Hematite-Included Quartz)

Quartz (Silicon Dioxide) with Lepidocrosite or Hematite inclusions (SiO2 + Fe2O3 · nH2O)

Rough Quartz

Quartz (Silicon Dioxide, SiO2)

Orange Quartz (Citrine Quartz)

Silicon Dioxide (SiO2)

Quartz (Milky or Cloudy variety)

Silicon Dioxide (SiO2)

Quartz

Silicon Dioxide (SiO2)

Citrine Quartz (Yellow Quartz)

Silicon Dioxide (SiO2) with iron impurities

Quartz Mineral

Silicon Dioxide (SiO2)

Quartz (Smoky Quartz variant)

Silicon Dioxide (SiO2)

Iolite-bearing Gneiss (Cordierite)

Cordierite (Mg2Al4Si5O18) in Gneiss matrix

Quartz Geode

Silicon Dioxide (SiO2)

Kimberlite

Kimberlite (Porphyritic Peridotite)

Obsidian

Volcanic Glass (70-75% SiO2)

Milky Quartz

Silicon Dioxide (SiO2)

Quartz Geode

Clear Quartz (Silicon Dioxide, SiO2)

Milky Quartz

Silicon Dioxide (SiO2)

Porphyritic Rhyolite

Porphyritic Rhyolite

Beryl (Variety: Aquamarine)

Beryllium Aluminum Cyclosilicate (Be3Al2Si6O18)

Quartz

Silicon Dioxide (SiO2)

Basalt with Plagioclase Feldspar

Basalt (mafic extrusive igneous rock) with plagioclase feldspar phenocrysts

Granite

Phaneritic Felsic Igneous Rock (composed of quartz, feldspar, and mica)

Granite

Granite (Felsic Plutonic Rock)

Chalcedony (Common Opal variant or Quartz)

Silicon Dioxide (SiO2)

Black Tourmaline

Schorl (Sodium Iron Aluminum Borosilicate Hydroxide); NaFe2+3Al6(Si6O18)(BO3)3(OH)3(OH)

Granite

Felsic Intrusive Igneous Rock

Smoky Quartz with Iron Inclusions

Silicon Dioxide (SiO2)

Dumortierite Quartz

Al7(BO3)(SiO4)3O3

Quartz Geode

Silicon Dioxide (SiO2)

Milky Quartz Pebble

Crystalline Silicon Dioxide (SiO2)

Quartz (Milky or Smoky variety)

Silicon Dioxide (SiO2)

Obsidian

Volcanic glass (SiO2 - Silicon Dioxide with impurities)

Ferruginous Quartz

Quartz (Silicon Dioxide) with Iron Inclusion, SiO2