300 Mill

In 1899 the Alaska Treadwell Gold Mining Company erected a 300 stamp mill at this site. This is the largest number of stamps ever installed under one roof, anywhere in the world. After the ore from the mine tunnels arrived in the stamp mill for crushing, each 1,020 pound stamp, dropping 8 ½ inches 98 times per minute, crushed six tons of ore daily to fineness that would allow the ore to pass, with a stream of water, through a wire screen with 40 holes per square inch. The pulverized ore fell onto copperplates coated with mercury. Free gold, amalgamated with the mercury, was collected and retorted (heated to separate the mercury from the gold). The pounding of the stamps made so much noise that people in the downtown Douglas Café had to shout to be heard. When the mills shut down for Christmas and the 4th of July, people said they could not sleep because it was so quiet. The rest of the ore was washed and shaken on the inclined vanner belt. The gold in the gold bearing ore was removed at first in the sulphurettes (chlorination) plant. In 1912 a more efficient cyanide plant was built. One wonders what might have caused the white, dead appearing, tree trunks on the hillside behind the buildings. Many of the trees had already been cut for underground supports and other mine uses. If you look at the woods, in this area, you will not see any trees more than 100 years old.

Getting There

Coordinates
Latitude: 58.271497
Longitude: -134.385121