History & Geology
The Amazing Mineral Tourmaline
December 2013 by Chris Ralph
It is a gemstone, and yet it is also closely associated with many types of metal ores. It's valuable itself but often points toward other valuable minerals—that is certainly something prospectors want to know more about!
Kennecott Copper Mine, Kennecott, Alaska
For approximately 30 years, the mines produced good ore, some so rich it was simply sent straight to bagging, bypassing milling and loaded directly on the rail cars.
Mining Pegmatite Deposits
With successively lower temperatures as the water mixture cools, new sets of minerals are formed and many of those stable at a higher degree of heat became subject to alteration as the temperature progressively moved lower.
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...
The Amazing Mineral Tourmaline
It is a gemstone, and yet it is also closely associated with many types of metal ores. It's valuable itself but often points toward other valuable minerals—that is certainly something prospectors want to know more about!
Gold Depositiion and Gradients of Placer Streams—Part II
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.
Ask The Experts
Q: Is there a correlation between fault zones and mineralization of economic metals?
Know Your District
We have to remember that the earliest miners were not geologists, but came from a variety of backgrounds. Their survival depended on finding enough gold so they worked hard and adapted to whatever challenges these new areas presented.
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