Alaska Hardrock Metal Mines Through Time
The scale of hardrock metals mining in Alaska is changing, the size of future mines (on the right) dwarfs that of current and historic mines in the state. The first large-scale mines appeared not long after statehood, but most gold mines were shut down during WWII and never re-opened. The deregulation of gold in 1971 allowed the price to increase and eventually more large gold mines opened in the state. The steady increase in the price of gold over the last decade in particular is driving large amounts of current development and exploration.
Calculations and Assumptions
Mines were included if the value of the metal exceeded $100 million by current market value for past production in the case of historic mines or estimated reserve size in the case of current and future mines. This figure depicts only hardrock mines, but it should be noted that a large amount of Alaskan gold has historically come from placer mines as well.
For all current and future mines, we combined "indicated" and "inferred" resources. See our coal terminology article for information about the technical meaning of these terms.
Caveats
There is no official database of historical mines in Alaska so it is possible that this analysis has missed some small mines.
We took estimated opening dates for Nixon Fork, Rock Creek, Donlin Creek, and Pebble from publicly available information as of August 2010 but could these could change. These mines may never re-open or begin construction. Projects with an "Unknown Opening Date" are exploration projects for which official resource estimates have been made.
Changes in the technology of gold extraction enable a modern mines to extract more gold from a given resource than a mine in the 19th century. If modern resource estimates had been applied to historical mines, those mines would presumably have had a larger resource base than what was actually mined. Some modern mines also use cyanide heap leaching to re-process old mine tailings to extract remnant gold; leaching is usually included in the indicated resources of a mine where relevant.
The estimated resource sizes of future mines have the potential to go up or down as additional deposits are discovered through exploration, and as the price of gold rises and falls.
Data for currently operating mines is a combination of historical production data and estimated resource data if available. For some current mines that opened within recent years, only the estimated resource data was used since historical production is only a fraction of that number. For Red Dog Mine and Greens Creek Mine, total historical production was unavailable and so was estimated by using production data from a number of a years and interpolating the missing data between those years.
More information
Detailed articles on many of these mines and exploration prospects can be found on our Metals Mining page.