Pyrophyllite

Unknown Owner

A good example for the species, radiating crystals of pyrophyllite on matrix. In great condition. This dates to the 1950s.The Montgomery County pyrophyllite district in North Carolina is centered on a series of massive, high-purity deposits located within the Carolina Slate Belt. Geologically, these deposits formed during the Late Proterozoic through the hydrothermal alteration of felsic volcanic rocks, such as tuffs and breccias, resulting in a mineral suite dominated by pyrophyllite along with associated andalusite, diaspore, and lazulite. This region is well-known for producing aesthetic, radiating stellate clusters of pyrophyllite crystals that are highly regarded by systematic collectors. Historically, mining and quarrying in the county began in the mid-19th century, with significant industrial development occurring in the early 1900s to supply the ceramics, refractories, and insecticide industries. The most prominent operations, such as the Glendon and Robbins mines, have seen various periods of activity throughout the 20th century, with some sites continuing production or maintaining active permits through 2026.