Metamorphic Rock (Specifically A Rock Composed Of Minerals)

Limonite (Iron Ore)

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

Garnet (Almandine)

Almandine, Fe3Al2(SiO4)3

Citrine Quartz

Silicon Dioxide (SiO2)

Citrine

Silicon Dioxide (SiO2)

Quartz with Limonite Staining

Silicon Dioxide (SiO2) with Hydrated Iron Oxide (FeO(OH)·nH2O)

Magnetite

Magnetite (Fe3O4)

Granite with Quartz Vein

Phaneritic Felsic Igneous Rock (composed of Quartz [SiO2], Feldspar, and Mica)

Rose Quartz

Rose Quartz (SiO2)

Granitic Pegmatite

Granite (with coarse-grained Quartz, Feldspar, and Mica components)

Grey Agate

Silicon Dioxide (SiO2) - Variety of Chalcedony

Emerald with Matrix (Emerald in Mica Schist)

Beryl (Be3Al2Si6O18) with Chromium/Vanadium impurities

Serpentine

Serpentinite (rock), Serpentine group minerals (e.g., Antigorite, Lizardite, Chrysotile)

Quartz Geode

Silicon Dioxide (SiO2)

Garnet

Almandine (Fe3Al2(SiO4)3)

Granite / Quartz Vein Rock

Granitoid with Quartz (SiO2)

Lapis Lazuli

Lapis Lazuli (Rock containing Lazurite, Calcite, and Pyrite)

Glaucophane Schist (Blueschist)

Blueschist (Glaucophane-bearing schist)

Gold-bearing Quartz

Auriferous Quartz (SiO2 with Native Gold inclusion)

Agate (Polished Nodule)

Agate (Silicon Dioxide, SiO2)

Quartz (Milky/Smoky variety)

Silicon Dioxide (SiO2)

Oolitic Limestone

Oolitic Carbonate (CaCO3)

Green Aventurine

Silicon Dioxide (SiO2) with inclusions

Vesicular Basalt with Xenocrysts

Mafic Igneous Plutonic/Extrusive Complex

Crushed Granite Gravel

Granite (composed primarily of Quartz, Alkali Feldspar, and Plagioclase Feldspar)

Quartz (Milky/Common)

Silicon Dioxide (SiO2)

Snowflake Obsidian (or similar porphyritic volcanic rock)

Obsidian with Spherulites (if glassy), or Porphyritic Rhyolite/Andesite (if crystalline groundmass)

Milky Quartz

Crystalline Silicon Dioxide (SiO2)

Yellow Aventurine

Quartz (SiO2) with iron-bearing inclusions

Chert (Jasper variation)

Silicon dioxide (SiO2)

Granite (with alteration)

Granite (Felsic intrusive igneous rock)

Quartz Pebble

Silicon Dioxide (SiO2)

Granite

Granite (phaneritic intrusive igneous rock consisting mainly of quartz, alkali feldspar, and plagioclase)

Yellow Quartz (Citrine or Iron-Stained Quartz)

Silicon Dioxide (SiO2)

Granodiorite

Granodiorite (Intermediate intrusive igneous rock)

Sandstone (likely Ferruginous)

Arenite (SiO2 with iron oxide impurities)

Olivine (Peridotite)

(Mg, Fe)2SiO4 (Magnesium Iron Silicate)

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

Silicon Dioxide (SiO2) - Cryptocrystalline Quartz

Basalt

Extrusive Mafic Igneous Rock (composed primarily of plagioclase, pyroxene, and olivine)

Tiger's Eye

Pseudomorph of Quartz after Crocidolite (SiO2 with iron inclusions)

Serpentinite (often containing Jadeite/Nephrite)

Antigorite-rich Serpentine Rock, (Mg, Fe)3Si2O5(OH)4

Quartz (Milky/Common)

Quartz (Silicon Dioxide, SiO2)

Chalcedony (River Stone)

Microcrystalline Quartz (SiO2)