Red balls of erythrite with white picropharmacolite. Acicular radiating sprays and spheres of picropharmacolite with reddish balls of Erythite. From a historical locality Wilhelm mine, Richelsdorf mining district, specimen is from 1975. Deposit : The Richelsdorf district is an ancient mining area, primarily known for its Permian copper shale (approx. 250 million years old) and hydrothermal barite veins (barytes) with cobalt, nickel and arsenic ores.Operation : Copper shale mining dates back to the 15th century and experienced its heyday in the 17th and 18th centuries. While copper shale mining in the region finally ceased in 1956, barite mining continued until 1963.Infrastructure : The Wilhelm mine essentially consisted of the two now abandoned shafts Wilhelm I and Wilhelm II , as well as the associated spoil heaps