Mineral In Metamorphic Rock

Muscovite Mica

Muscovite (Potassium Aluminum Silicate) - KAl2(AlSi3O10)(F,OH)2

Likely schist or foliated metamorphic rock

Mica schist, possibly amphibole-bearing; composition likely quartz, feldspar, biotite and/or hornblende

Slate with Quartz Vein

Foliated Metamorphic Rock (Mainly Quartz, Muscovite, Chlorite)

Biotite Schist

Metamorphic Rock (Schist)

Quartzite with inclusions

Metamorphic Rock (Mainly SiO2)

Banded Gneiss

Gneiss (Metamorphic rock)

Banded gneiss (likely garnet-biotite or quartz-feldspar gneiss)

Gneiss; predominantly quartz (SiO₂), feldspar, and dark biotite/amphibole

Banded Gneiss with Quartz Vein

Foliated Metamorphic Rock (Gneiss)

Foliated metamorphic rock, likely mica schist

Muscovite- or biotite-bearing schist, commonly quartz–feldspar schist

Banded metamorphic rock, likely gneiss or metasedimentary slate

Quartz–feldspar–mica gneiss (tentative), possibly containing iron-oxide veins

Gneiss (Banded Gneiss Cobble)

Gneiss

Pyrite in Matrix (Gold-colored Chalcopyrite or Pyrite)

Iron Sulfide (FeS2) / Copper Iron Sulfide (CuFeS2)

Weathered quartz-rich metamorphic rock, likely quartzite

Quartzite, predominantly crystalline SiO₂, possibly micaceous or feldspathic

Likely banded metamorphic rock, possibly schist or gneiss

Micaceous schist/gneiss; identification is limited from the photograph

Quartz-rich metamorphic rock, likely quartzite

Quartzite; predominantly crystalline SiO₂, possibly with iron-oxide staining and minor feldspar or mica

Agate

Chalcedony (SiO2) with impurities

Quartz-rich metamorphic rock, likely quartzite

Quartzite; predominantly microcrystalline quartz (SiO₂), with minor feldspar, mica, and iron-oxide staining

Foliated mica-rich metamorphic rock, likely schist

Mica schist; predominantly quartz, feldspar, and biotite/muscovite mica

Weathered quartz-rich metamorphic rock

Probable quartzite or quartz-rich gneiss; predominantly SiO₂ with feldspar and minor mica/iron oxides

Mica Schist / Granite

Mica Schist (Silicate metamorphic rock)

Likely serpentine

Serpentine-group minerals, chiefly antigorite, lizardite, or chrysotile; approximate formula Mg₃Si₂O₅(OH)₄

Small dark mineral or rock fragment

Undetermined; possibly a dark mafic mineral such as biotite or magnetite

Moonstone

Orthoclase (Potassium Aluminum Silicate), Formula: (K,Na)AlSi3O8

Green Aventurine

Silicon Dioxide (SiO2) with inclusions of Fuchsite (K(Al,Cr)2(AlSi3O10)(OH)2)

Quartz Vein in Hematitic Siltstone

Hydrothermal Quartz (SiO2) in Ferriferous Matrix

Small quartz-rich pebble, possibly milky quartz

Quartz (silicon dioxide, SiO₂)

Tumbled green aventurine quartz

Aventurine quartz, silicon dioxide (SiO₂) with dispersed fuchsite or other mica inclusions

Garnet in Schist or Pegmatite

Almandine Garnet (Fe3Al2(SiO4)3) in host rock

Schist

Mica Schist

Dark metamorphic rock, likely slate or phyllite

Foliated metapelite; commonly mica-rich quartz–clay mineral assemblage

Gneiss

Gneiss (Metamorphic rock of variable composition, typically SiO2 rich)

Weathered mica-rich schist

Muscovite–biotite schist, possibly quartz-bearing

Mixed tumbled river pebbles and beach stones

Polymictic alluvial gravel; components include quartz, chert, jasper, sandstone, and altered volcanic rocks

Quartz Crystal Cluster on Matrix

Silicon Dioxide (SiO2)

Quartz (Orange/Pink variety)

Silicon Dioxide (SiO2)

Quartz Crystal

Silicon Dioxide (SiO2)

Quartz with Mica/Host Rock

Silicon Dioxide (SiO2) with Phyllosilicates

Glaucophane Schist (Blueschist)

Blueschist facies metamorphic rock

Gneiss (specifically Granitic Gneiss)

Gneissic Metamorphic Rock

Banded Gneiss

Gneiss (High-grade regional metamorphic rock)

Gneiss

Metamorphic Gneiss

Blue-gray metamorphic rock, likely slate or schist

Foliated phyllite–schist; chiefly quartz, mica, and chlorite (exact identification requires testing)