History & Geology
Critical Minerals: Tungsten
July 2017 by Chris Ralph
Because tungsten minerals are heavy, exploration can be done using stream sediment samples. Prospectors looking for gold have found scheelite or wolframite in their placer concentrates, and in some cases this has led them to make important tungsten finds.
The Golden Streams of Butte County, California
Even though these were some of the earliest placer deposits to be worked, there is still plenty of gold left today—it just takes more work to recover. Knowing about the old locations where gold has been found is the first step to success.
One of the Richest Beaches Ever Mined
Everyone has heard of the golden beach at Nome, but Nome did not have the richest beach.
Ask The Experts
Sulfides and oxides—what's the difference between the two?
Prospecting With The Help of Fluvial Geomorphology
Quiz yourself about the stream in figure 5. Based on your previous knowledge of where gold is found in a stream and in this article, where do you think you will find the most gold?
The Bawl Mill
• Do as I say, not as I do...
• By the numbers...
Why Did This Silver Mine Close? - Pt III
Narrowing down a closure date will allow you to check the commodity price during that time and possibly confirm that a low price, rather than a lack of ore, was the driving force that closed the operation.
Critical Minerals: Titanium—Part II
There are both hard rock and beach sand types of titanium deposits, but the hard rock deposits need to be at least 10 percent titanium while the beach sands often are economic with only two or three percent titanium.
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The Bawl Mill
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• Ask The Experts: Sulfides and fluxes
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• The "Madonna Nugget"—A Weekend Hunt to Remember
• The Goldfield Mining District, Nevada—Part II
• Sunset Sunbaker
• A Prospecting Adventure in Mexico
• Police Urge Author to End Treasure Hunt
• Melman on Gold & Silver
• Mining Stock Quotes and Mineral & Metal Prices
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