The huge open-pit mine planned by Northern Dynasty Minerals Ltd. may be further along the road to reality, but other mining corporations also are eyeing a slice of the porphyry pie beneath Southwest Alaska.
And with good reason.
The Alaska Miners Association said Alaska has a history of being "elephant country" when it comes to sizable deposits, pointing to the success of the Greens Creek Mine on Admiralty Island, which has produced 7.6 million ounces of silver, 37,000 ounces of gold and tons of lead-zinc concentrates, and the Red Dog Mine in the Brooks Range, which has produced more than 550,000 tons of zinc and lead. Those mines are expected to produce for decades.
The association also lauds Alaska's wealth of low-sulfur coal, totaling as much as all the deposits in the rest of the United States combined.
"Many other elephants are known to exist," an AMA Web site article says. "Some are being re-evaluated for application of modern mining and extractive technologies. Others are being evaluated for infrastructure development."
While Congress has set aside large tracts of Alaska for parks and preserves, the AMA notes that in the state "there is still a tremendous amount of federal, state and private Native corporation lands" available for minerals development.
State land drawing the most attention these days is the Pebble porphyry, ringing an ancient volcanic caldera northwest of Iliamna where Northern Dynasty Minerals Ltd. hopes to begin developing its open pit mine in 2007. NDM isn't alone in that interest.
Other mining companies showing great interest and holding claims in the Pebble porphyry include Liberty Star Gold Corp., whose subsidiary, Big Chunk Corp., owns 981 claims totaling 153,000 acres of what they call the "Big Chunk Caldera." Liberty's holdings, together with those of Northern Dynasty, form a kind of ring of claims on the outer edges of the caldera, but Liberty's significantly larger acreage covers three-quarters of the total.
According to Liberty, deposits of the targeted minerals (gold, copper and molybdenum) "almost always occur in clusters" in the outer areas of these collapsed extinct volcanoes. New discoveries "strongly indicate" that additional deposits likely are to occur within Liberty's "strategically positioned claim holdings," Liberty said.
Liberty Star is conducting a large-scale aeromagnetic survey of its Big Chunk ground, the company said. From that and ground-level work to come, Liberty expects to locate "one or more thinly-covered, large, disseminated porphyry copper-gold molybdenum mineral zones similar to the Pebble deposit and other deposits discovered to date in the Pebble zone," public company documents say.
Another company with interest in the region is Full Metal Minerals Ltd., a Canadian company, which currently has nine significant gold and copper-gold properties in Alaska. Its Pebble South Copper-Gold Project is adjacent to NDM's Pebble (partly to the southwest, partly to the northwest) and covers nearly 91,500 acres. The company recently completed an exploration program and says it identified multiple new targets.
According to the Alaska Department of Natural Re-sources, two other companies own claims at or near the Pebble porphyry, including Alaska Earth Sciences, which DNR says holds claim to about 90,000 acres, and Furio Resources, which owns about 4,000 acres to the southwest.
The target porphyry is within the environmentally sensitive Bristol Bay Watershed. According to data available on the Alaska Division of Mining, Land and Water Web site, there are now at least 743 square miles (475,600 acres) of state mining claims in the watershed.
Scott Brennan, director of Alaska for Responsible Mining, says the total area in which various claims are disbursed covers 7,800 square miles, or roughly 5 million acres of the watershed.
"This is equivalent to the land area of the state of Massachusetts," he said.
It is also roughly the size of the portion of Cook Inlet within the Kenai Peninsula Borough, or about half the borough's land mass.
Peninsula Clarion ©2015. All Rights Reserved.