Zinc now accounts for only 30 percent of revenue from “Zinc” mines, that is zinc mines in the broadest sense, as polymetallic deposits become proportionally a more important source of zinc and contributor to zinc production. In some of many of these precious metal dominant polymetallic mines zinc is often not much more than a by-product and will be produced anyway. The economics of a significant slug of zinc mine production is therefore vulnerable to some greater or lesser extent to a drop in the price of precious metals. If these precious-metal polymetallic mines become unprofitable to mine because of a lower gold price for example then we lose the associated zinc production. If precious metal prices were to rise and increase ore-value then this might subsidise the continual production of zinc or even expansion of production from these mines.
