Metamorphic Or Sedimentary Depending On Local Grade

Mica Schist

Mica Schist (primarily Muscovite or Biotite sheet silicates)

Slate

Foliated Metamorphic Rock

Mica Schist

Schist (muscovite-biotite schist)

Schist

Mica Schist

Quartzite

Quartzite (SiO2)

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Schist

Mica Schist (Metamorphic Rock)

Anthracite Coal

Anthracite (Carbon-based organic sedimentary rock transitioned to metamorphic)

Granite Gneiss

Gneiss (High-grade Metamorphic Rock)

Schist

Mica Schist

Milky Quartz Vein in Host Rock

Silicon Dioxide (SiO2)

Slate with Quartz

Low-grade Metamorphic Slate with SiO2 inclusions

Pyrite (Fool's Gold)

Iron Sulfide (FeS2)

Slate

Slate (foliated metamorphic rock)

Eclogite

Eclogite (Omphacite + Pyrope)

Mica Schist

Mica Schist (KAl2(AlSi3O10)(OH)2 / K(Mg,Fe)3(AlSi3O10)(OH)2)

Mica Schist

Muscovite-Biotite Schist

Slate

Low-grade Metamorphic Rock (composed of quartz, illite, chlorite)

Banded Agate (with possible Chalcedony layers)

Silicon dioxide (SiO2)

Chlorite (Small Flakes/Sand)

Chlorite Group (Magnesium Iron Aluminum Silicate Hydroxide - (Mg,Fe)3(Si,Al)4O10(OH)2·(Mg,Fe)3(OH)6)

Greenschist (Chlorite Schist)

Greenschist (Metamorphic rock dominated by chlorite, actinolite, and epidote)

Diamond (as set in a gold ring)

Carbon (C)

Pyrite (Fool's Gold)

Iron Disulfide (FeS2)

Schist

Mica Schist

Black Tourmaline

Schorl (NaFe3Al6(BO3)3Si6O18(OH)4)

Green Quartz (including Prase or Aventurine variants)

Silicon Dioxide (SiO2) with inclusions (likely Actinolite or Chlorite)

Tourmaline (likely Schorl)

Tourmaline Group Mineral (e.g., Schorl for black varieties); (Na,Ca)(Li,Mg,Fe,Mn,Al)3Al6(BO3)3Si6O18(OH)4

Unakite

Epidotized Granite

Ruby (Corundum)

Corundum (Aluminum Oxide) with chromium trace elements, Al2O3

Yellow Diamond

Diamond (Carbon, C)

Prehnite

Calcium aluminum silicate hydroxide - Ca2Al(AlSi3O10)(OH)2

Alexandrite

Chrysoberyl (BeAl2O4 with Chromium impurities)

Conglomerate

Conglomerate

Yellow Agate

Silicon Dioxide (SiO2)

Pink Feldspar

Orthoclase Feldspar (KAlSi3O8)

Marble

Recrystallized Calcite (CaCO3) or Dolomite (CaMg(CO3)2)

Quartzite

Quartzite (SiO2 silicon dioxide)

Aquamarine

Aquamarine (Beryl variety) - Be3Al2(Si6O18)

Slate with Red Sandstone Landscaping Rock

Foliated Pelitic Metamorphic Rock (Slate) and Ferruginous Sandstone

Schist

Crystalline Schist (often containing Muscovite, Biotte, or Quartz)

Native Gold (in Jewelry)

Gold (Au)

Biotite Mica

K(Mg,Fe)3AlSi3O10(OH)2