The “Zch” Rock group which covers most of the Plott Balsams is known as the CopperHill Formation. Consists of mostly metagraywacke with smaller proportions of mica schist, metaconglomerate, quartzite, and meta-arkose. Metagraywacke and mica schist are interbedded throughout formation. Thickness is estimated at between 2000 and 5000 ft, but accurate measurements are hampered by sparse outcrops and structural complexity. Along boundary, metagraywacke and mica schist of Copperhill are interbedded with staurolite-mica schist and metaquartz conglomerate of overlying Hughes Gap formation. Transition zone is a few hundred feet thick. Age is Precambrian. This rock is acidic and considered highly unstable due to the potential for weathering…in particular in the slate form. (“Zchs”) Any soil above this type of rock is also considered unstable. The map does show a lot colluvium debris on the North side of the mtn likely from historic landslides.
The Copperhill formation (Named after the town of Copperhill in TN) can have massive deposits of sulfides of copper, iron, and zinc. The minerals found in the Copperhill formation in order of abundance include pyrrholite, pyrite, chalcopyrite, sphalerite, magnetite, along with traces of silver and gold. Garnet is also found in this formation.
Mount Lyn Lowry North Carolina 