Igneous, Sedimentary, Metamorphic, Mineral

Hematite

Hematite (Fe2O3)

Banded Gneiss

Gneiss (Metamorphic silicate rock)

Gneiss

Gneiss

Gneiss (specifically Banded Gneiss)

Gneiss

Gneiss (specifically Granitic Gneiss)

Gneiss (composed primarily of Quartz, Feldspar, and Biotite/Amphibole)

Pyrite

Iron Sulfide (FeS2)

Clear Quartz

Silicon Dioxide (SiO2)

Blue Calcite

Calcium Carbonate (CaCO3)

Feldspar

Potassium Feldspar (KAlSi3O8)

Pyrite

Iron Sulfide (FeS2)

Pyrite

Iron Sulfide (FeS2)

Hematite (Tumbled)

Iron(III) oxide (Fe2O3)

Gneiss

Gneiss

Gneiss

Gneiss (High-grade metamorphic rock)

Gneiss

Gneiss (High-grade Regional Metamorphic Rock)

Gneiss (likely Granitic Gneiss)

Gneiss

Banded Gneiss

Gneiss (high-grade metamorphic silicate rock)

Gneiss

Gneiss

Quartz pebble

Silicon Dioxide (SiO2)

Gneiss

Gneiss (High-grade regional metamorphic rock)

Gneiss

Gneiss

Gneiss

Gneiss (High-grade metamorphic rock)

Gneiss

Gneiss (Metamorphic Rock)

Milky Quartz

Silicon Dioxide (SiO2)

Gneiss

Gneiss

Gneiss

Gneiss

Gneiss

Gneiss

Banded Gneiss

Metamorphic Gneiss (High-grade regional metamorphism specimen)

Quartz Pebble

Crystalline Silica (SiO2)

Gneiss (with Granite/Pegmatite Vein)

Foliated Metamorphic Rock (Quartz-Feldspar Gneiss)

Amphibolite (specifically Hornblende Schist/Gneiss)

Amphibole-rich Metamorphic Rock

Gneissic Granite (River Stone)

Protomylonite or Gneiss

Milky Quartz

Silicon Dioxide (SiO2)

Feldspar

KAlSi3O8 - NaAlSi3O8 - CaAl2Si2O8

Quartz (Tumbled/Water-worn)

Silicon Dioxide (SiO2)

Pyrite

Pyrite (FeS₂)

Fuchsite Schist with Quartz

Chromian Muscovite [K(Al,Cr)2(AlSi3O10)(OH)2] Schist

Banded Gneiss

Gneiss (Metamorphic Rock)

Quartz Pebble

Silicon Dioxide (SiO2)

Banded Gneiss

Gneiss (High-grade regional metamorphic rock)

Magnetite (Lodestone variety)

Magnetite (Iron(II,III) oxide, Fe3O4)

Pyrite on Quartz

Iron Sulfide (FeS2) on Silicon Dioxide (SiO2)