(W.H. Case, AEL&P Collection)
Gold was discovered in Juneau at what is now known as Gold Creek, in 1880. The early mining efforts were placer mines, which used large water jets to wash the gravel through sluices to separate it from the gold. Most of the placer mining along Gold Creek in the Silver Bow Basin was finished by the 1890s, and the miners' attention was drawn to the lode, or hard-rock gold deposits. Miners soon discovered that the gold ore around Juneau was relatively low grade. Yield from the mines ranged from 10-20 tons of ore per ounce of gold. To run a profitable operation, mining had to be done very efficiently and on a very large scale.
The smaller mining operations in the Juneau area began consolidating and by 1911 there were three large mines operating in the Juneau area: the Treadwell Mine on Douglas Island; the Alaska Juneau or AJ Mine, with a mill operating near downtown Juneau; and the Alaska Gastineau Mine operating in the community of Thane near Sheep Creek. Each of these mines was at one time the largest or most efficient gold mine in the world.
The Treadwell Mine ceased the bulk of its operations after a catastrophic collapse and flooding of its underground workings in 1917. The Alaska Gastineau Mine shut down in 1921 due to ore that was too low grade to mine cost effectively. The AJ Mine closed in 1944 because the high cost of labor and the low cost of gold made the operation unprofitable.