Metamorphic

Quartzite

Quartzite (primarily SiO2)

Quartzite River Rock

Quartzite (primarily SiO2)

Slate

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

Anthracite Coal

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

Quartz Vein with Host Rock (Greywacke/Siltstone)

Silicon Dioxide (SiO2) within Clastic Sedimentary/Metamorphic Matrix

Gneiss (specifically Biotite Gneiss)

Gneiss (high-grade metamorphic rock primarily composed of Silicates)

Slate

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

Slate

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

Mica Schist

Mica Schist (Schistose metamorphic rock rich in Muscovite/Biotite)

Schist

Schist (various mineralogical compositions including mica, chlorite, talc, etc.)

Quartzite

Quartzite (primarily SiO2)

Mica Schist

Mica Schist (primarily Muscovite and Biotite composition)

Quartzite Beach Pebble

Quartzite (primarily SiO2)

Unakite

Epidotized Granite

Epidote with Quartz and Feldspar

Ca2(Al2,Fe3+)(SiO4)3(OH) (Epidote complex)

Gneiss

Gneiss (High-grade Regional Metamorphic Rock)

Slate

Slate (Low-grade regional metamorphic rock)

Gneiss

Gneiss (High-grade Regional Metamorphic Rock)

Quartzite (Iron-stained River Rock)

Metamorphic Rock consisting primarily of Quartz (SiO2)

Red Quartzite

Metamorphic Rock (rich in SiO2 with hematite inclusions)

Gneiss

Gneiss (High-grade Regional Metamorphic Rock)

Foliated Gneiss (River-Worn Pebble)

Gneiss (High-grade Regional Metamorphic Rock)

Quartzite Pebble

Metamorphic rock predominantly composed of Quartz (SiO2)

Banded Gneiss

Gneiss (High-grade regional metamorphic rock)

Gneiss

Gneiss (High-grade regional metamorphic rock)

Banded Gneiss

Gneiss (High-grade Regional Metamorphic Rock)

Gneiss

Gneiss (High-grade Regional Metamorphic Rock)

Gneiss

Gneiss (High-grade Regional Metamorphic Rock)

Gneiss

Gneiss (High-grade regional metamorphic rock)

Banded Gneiss

Gneiss (High-grade regional metamorphic rock)

Gneissic Schist

Foliated Metamorphic Rock (Schist/Gneiss transition)

Gneiss

Gneiss (High-grade Regional Metamorphic Rock)

Schist

Mica Schist (Medium-grade metamorphic rock)

Quartzite

Metamorphic rock predominantly composed of Quartz (SiO2)

Red Quartzite River Stone

Metamorphic Rock (composed mainly of Quartz, SiO2)

Quartzite (Milky)

Metamorphic rock predominantly composed of Quartz (SiO2)

River Cobble (Salt and Pepper Gneiss)

Gneiss (High-grade regional metamorphic rock)

Gneiss with Orthoclase Feldspar

Gneissic Metamorphic Rock with K-Feldspar inclusions

Gneiss

Gneiss (High-grade Regional Metamorphic Rock)

Quartz on Schist

Silicon Dioxide (SiO2) on Foliated Metamorphic Rock

Banded Gneiss

Gneiss (High-grade regional metamorphic rock)

Banded Gneiss

Gneiss (High-grade Regional Metamorphic Rock)