An Analysis of Metal Distribution and Zoning in the

Mineralization is localized in a series of emanative centers which trend parallel with, and lie adjacent to the granite-sediment contact. Some areas of the original granite intrusion surface appear to contain series of minor ridges and troughs, whose axial trends also parallel the main contact directions, i.e., N.N.W. and E.N.E. Several major mineralization centers are situated adjacent to E.N.E.-trending ridges, and tend to be sited on the northern flanks. It is suggested that original ridge and cuspate structures on the granite surface played a significant role in localizing the emanative centers. Two phases of mineralization are suggested, an early tin-tungsten phase associated with greisenization, and a later polymetallic phase. The latter is often zoned, with an inner tungsten zone passing outwards into tin, copper, and lead zones. Development of the zonal sequence varies from center to center, i.e., one or more zones may be absent, and considerable superimposition occurs. It is possible in some areas that a separate lead-zinc-silver mineralization phase may occur