Winning the Metal: Ore Mills of the West
For hard rock, stamps might weigh as much as 750 pounds, and water to the tune of 150-200 gallons an hour was fed into each stamp to produce a slick pulp. It has been estimated that roughly ninety per cent of quartz bearing minerals were crushed by stamp mills. By 1875, California's Gold Rush country had nearly 400 mills operating.
WhatsApp: +86 18221755073