Metamorphic (Low Grade)

Serpentine

Serpentine Group (Mg,Fe,Ni,Al,Zn,Mn)2-3(Si,Al,Fe)2O5(OH)4

Muscovite Mica

Muscovite: KAl2(AlSi3O10)(OH)2

Greenschist

Greenschist (Chlorite-actinolite schist)

Greenschist

Chlorite schist (Metamorphic rock dominated by chlorite, epidote, and actinolite)

Arfvedsonite in Quartz (also labeled as Astrophyllite or Nuummite by collectors)

[Na][Na2][Mg4Fe2+](Si8O22)(OH)2 in SiO2

Orthoclase Feldspar

KAlSi3O8 (Potassium Aluminum Silicate)

Pink Opal (Common Opal)

Amorphous Hydrated Silica (SiO2·nH2O)

Natural Gemstone Cabochons (Ruby, Moonstone, Emerald, Citrine)

Ruby (Al2O3:Cr), Moonstone (KAlSi3O8), Emerald (Be3Al2(SiO3)6:Cr), Citrine (SiO2)

Bloodstone (Heliotrope)

Silicon dioxide (SiO2) with Hematite inclusions

Lepidolite

Lepidolite (K(Li,Al)3(Al,Si,Rb)4O10(F,OH)2)

Gneiss

High-grade foliated metamorphic rock

Gneiss

Gneiss (High-grade regional metamorphic rock)

Schist

Mica Schist

Mica Schist

Mica Schist (primarily Muscovite [KAl2(AlSi3O10)(OH)2] or Biotite)

Verde Antique Marble (Serpentinite)

Serpentinite (composed mainly of Serpentine group minerals, Mg3Si2O5(OH)4)

Serpentine

Serpentinite (Mg, Fe, Ni, Al, Zn, Mn)3(Si, Al, Fe)2O5(OH)4

Serpentinite

Serpentinite (composed primarily of Serpentine minerals: Mg3Si2O5(OH)4)

Gneiss

Metamorphic rock of high-grade regional metamorphism

Schist with Quartz Vein

Mica Schist with Crystalline Quartz (SiO2)

Schist

Mica Schist (contains muscovite/biotite and quartz)

Gneiss (specifically Granitic Gneiss)

Gneissic Metamorphic Rock

Peridotite (with Olivine and Pyroxene)

Ultramafic Magmatic Rock (Primary minerals: (Mg, Fe)2SiO4 and (Ca, Mg, Fe)2Si2O6)

Banded Gneiss

Gneiss (High-grade Metamorphic Rock)

Gneiss

High-grade metamorphic rock (Gneiss)

Gneiss

Gneiss (High-grade metamorphic rock)

Gneiss

Gneiss (High-grade Metamorphic Rock)

Gneiss

Gneiss (High-grade metamorphic rock)

Gneiss

Gneiss (High-grade metamorphic rock)

Gneiss

Gneiss (High-grade metamorphic rock)

Gneiss

Gneiss (high-grade metamorphic rock)

Gneiss

Gneiss (High-grade metamorphic rock)

Gneiss

Gneiss (High-grade metamorphic rock)

Pyrite (Fool's Gold)

Iron Sulfide (FeS2)

Coal (most likely Bituminous or Anthracite)

Bituminous Coal (Grade of Coal), Anthracite (Grade of Coal)

Zebra Jasper (usually a trade name for Serpentine or Basalt blend)

Antigorite/Chrysotile (Serpentine family) - Mg3Si2O5(OH)4

Schist

Mica Schist (Medium-grade metamorphic rock)

Turquoise (Dyed Howlite or Magnesite imitation)

Hydrated phosphate of copper and aluminum / CuAl6(PO4)4(OH)8·4H2O

Iolite-bearing Gneiss (Cordierite)

Cordierite (Mg2Al4Si5O18) in Gneiss matrix

Nephrite Jade

Ca2(Mg,Fe)5Si8O22(OH)2

Nuummite

Orthoamphibole (Anthophyllite-Gedrite composition)

Gneiss

Gneiss (Metamorphic rock composed primarily of quartz, feldspar, and mica)

Mica Schist

Mica Schist