Igneous And Metamorphic

Slate

Slate (Foliated metamorphic rock consisting mainly of quartz and muscovite or illite)

Stiped Slate Beach Pebble

Low-grade Metamorphic Slate with Quartz Vein (SiO2 on Phyllosilicate base)

Slate

Foliated Metamorphic Rock (primarily composed of quartz, illite, chlorite, and micas)

Rose Quartz

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

Quartzite

Quartzite (SiO2)

Quartzite

Quartzite (primarily SiO2)

Green Quartzite (Aventurine-like)

Quartzite (primarily SiO2 with trace Fuchsite mica inclusions)

Schist

Mica Schist (primarily Muscovite and Quartz)

Gold Ore in Quartz

Native Gold (Au) in Quartz (SiO2) matrix

Rough Tanzanite

Zoisite (Ca2Al3(SiO4)3(OH))

Quartz (Milky Quartz)

Silicon Dioxide (SiO2)

Milk Quartz (Vein Quartz)

Quartz (Silicon Dioxide, SiO2)

Quartzite

Quartzite (primarily SiO2)

Granite or Porphyritic Igneous Rock (weathered)

Granitoid

Jade (likely Nephrite or Jadeite)

Nephrite (Ca2(Mg,Fe)5Si8O22(OH)2) or Jadeite (Na(Al,Fe3+)Si2O6)

Slate

Slate (Regional metamorphic rock composed primarily of quartz, illite, and chlorite)

Mica Schist

Mica Schist (Composition typically includes Muscovite KAl2(AlSi3O10)(OH)2 and Quartz SiO2)

Granite (Phaneritic Igneous Rock)

Granite

Milky Quartz (with Iron Oxide staining)

Quartz (Silicon Dioxide - SiO2)

Shale

Shale (comprised mostly of clay minerals and quartz)

Quartz (Milky or White Quartz)

Silicon Dioxide (SiO2)

Lapis Lazuli (polished cabochon)

Lazurite-rich metamorphic rock (approx. Na6Ca2Al6Si6O24(SO4,S,Cl)2)

Slate

Slate (foliated metamorphic rock, primarily composed of quartz, illite, chlorite, and micas)

Fluorite-Gedrite in Quartz (Schist)

Fluorite (CaF2) with Gedrite in Quartz/Feldspar Matrix

Quartz (Druzy) in host rock

SiO₂ (Silicon Dioxide) as Quartz, with unspecified host rock components (likely silicates and iron oxides)

Quartz Druze (Crystalline Quartz)

Silicon Dioxide (SiO2)

Milky Quartz

Silicon Dioxide (SiO2)

Jade (Nephrite or Jadeite)

Nephrite: Ca2(Mg,Fe)5Si8O22(OH)2 (amphibole mineral); Jadeite: NaAlSi2O6 (pyroxene mineral)

Rhodonite

Rhodonite (MnSiO3)

Moonstone

Orthoclase Feldspar ((K,Na)AlSi3O8) with Albite

Jadeite Jade

Jadeite (NaAlSi2O6)

Galena

Lead(II) sulfide (PbS)

Peach Aventurine

Silicon Dioxide (SiO2) with Hematite/Goethite inclusions

Costume Jewelry Gemstones (Emerald-imitation and semi-precious beads)

BeCuAl6Si6O18 (Beryl structure), frequently simulated by glass or synthetic spinel

Green Aventurine

Silicon Dioxide (SiO2) with Fuchsite inclusions

Blue Dumortierite Quartz

Dumortierite in Quartz (AlAl6BSi3O12(O,OH)3)

Tiger's Eye (Rough)

Pseudomorph of Quartz after Crocidolite (SiO2)

Pyrite (Fool's Gold)

Iron Disulfide (FeS2)

Green Aventurine

Silicon Dioxide (SiO2) with Fuchsite inclusions

Green Aventurine

Silicon Dioxide (SiO2) with Fuscite inclusions

Specular Hematite

Hematite (Fe2O3)

Green Aventurine

Silicon dioxide (SiO2) with inclusions of Fuchsite mica