An effort is made to recover as much economically mineable gold as possible.
Mining underground is expensive.
A feasibility study will reveal the economic viability of such an operation. This quality makes these deposits attractive to smaller mining companies as they provide quick payback at high rates of return on moderate amounts of investment capital. The major mining companies prefer to mine large scale epithermal deposits which are suitable for open pit operations. These projects tend to be long term and a vast amount of capital investment is needed in the initial stages. This type of ore deposit is particularly attractive when base metal prices are depressed, because of high precious metal values with little or no base metal content.