They are crushed to egg-size in a rock-breaker, and pulverized to pass a 40-mesh sieve in a California stamp-mill, which treats in 24 hours about 3 tons per stamp. A 10-stamp mill is fed by one rock-breaker, and discharges the liquid pulp into 10-15 wooden settling tanks, 9 by 5 by 8 ft., the settled contents of which are shovelled out and charged into the pans.
In the Cazo, Caldron or Hot process the pulverized silver ore is boiled in a copper-bottomed wooden vat, first with brine until the silver has been reduced by the copper, and then with quicksilver.
In England, Kimmeridge Clay, Lias clays, London Clay and pulverized shale and slate are all employed for this purpose.
Krohnke into Copiapo, Chile, in 1860, the silver mineral of the pulverized ore is decomposed in a revolving barrel by a hot solution of cuprous chloride in brine in the presence of zinc or lead and quicksilver (see B.
In 1791 France was pulverized into innumerable administrative atoms incapable of cohesion; and the result was that Paris became more than ever the brain and nerve-centre of France.