A rock mass heavily intersected by a dense network of small, irregular ore-bearing veins. Because the individual veins are too narrow and erratic to mine separately, the entire fractured rock body is usually extracted as a single bulk mass. This formation is typical of porphyry copper and tin deposits.
Heard on the job
The drill core shows a solid quartz-molybdenite stockwork starting at fifty meters down.
Insider tip
The term comes from the historic German practice of mining these massive deposits in stories or floors.