History & Geology
Gold Depositiion and Gradients of Placer Streams—Part II
July 2012 by Jim Halloran
The steeper the gradient is, the more potential erosive power to move gold and other bedload sediments, and the more power to remove obstacles to flow.
The Mineral Range Districts of Utah
Most of the commercial mineral deposits are on the south and southwest part of the range between Minersville and Milford, though small amounts of gold and silver have also been found in iron-rich outcrops in the basalt to the south of Milford.
Testing Ores for Free Gold
I get a number of questions from people about testing and treating hard rock ores. The simplest way, but also an expensive one, is to just have an assay test done by an independent assay firm. As an alternative...
Copper Deposits of Alaska
Only the famous Kennecott copper mine was able to continue operating through the Depression owing to the exceptional richness of its ore.
The Giant King Mine
Most gold-bearing veins in this region are controlled by fractures associated with the Melones Fault, a late Cretaceous structure that is 108 to 127 million years old.
The Goldfield Mining District, Nevada—Part II
The majority of the gold produced in Goldfield has come from ores that are close enough to the surface to be oxidized by the air. This oxidized ore is normally a soft, shattered, earthy material usually stained yellow to brown by oxides of iron.
Undiscovered Placer Deposits in Alaska
These conditions don’t just apply to Alaska and the Yukon; they apply to western Canada and even to the mountainous western United States.
Subscription Required:
The Bawl Mill
• The Life of an Independent Prospector
• Gold in Guyana—Part I: Porknocking on the Puruni River Road
• That Something Extra
• Prospecting for Copper Ores—Part II
• Metallic Trash—Scourge of the Prospector
• Gold Mining Boom in the Carolinas
• California Suction Dredging Update
• Mine, Baby, Mine!
• Hecla to Reopen Lucky Friday Mine
• Nova Scotia Shows It's Serious About Jobs & Mining
• Melman on Gold & Silver
• Mining Stock Quotes and Mineral & Metal Prices








