History & Geology
The Golden Days of Julian, California
October 2011 by Frank Lorey III
Some scattered reports say that gold may have been washed from streams here as early as the 1840s, but the undisputed major discovery came in 1870.The Wild Rush to Find More Cobalt—Part I
While some future cobalt will come from recycling lithium batteries and other products, the coming huge need for cobalt is virtually a perfect storm of heavy demand and insufficient supply.
The Silver, Gold and Gemstones of Candelaria, Nevada
The Candelaria area is of interest to prospectors not just for silver, gold and other metals, but also for the beautiful gemstones found there.
Gold Deposition and Gradients of Placer Streams—Part I
When placer miners from the gold rush era began experimenting with the slope of their sluices, they must have pondered the ideal slope for trapping gold in a creek bed too. Logic suggests the same is true for streams...
The Beatty Mining District of Nevada
The Beatty Mining District in south-central Nevada has been one of the most productive Mining Districts in the state, producing millions of ounces of gold together with silver, fluorite, mercury and other valuable minerals.
The Birimian Greenstone Belts of West Africa
A few years ago I had a tremendous opportunity to visit Australia and hunt for gold there. The geology of the gold deposits there was somewhat different from what I was used to here in the US. I learned a lot about greenstone belt gold deposits while prospecting them in person, and it was an amazing trip.
Calcite and Limestone
The other distinguishing feature of calcite has to do with its chemistry. Geologists sometimes take a small bottle of dilute hydrochloric acid out into the field with them because calcite reacts with acids to make a bubbly foam.
Critical Minerals: Tungsten
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.
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The Bawl Mill
• Legislative And Regulatory Update
• Ask The Experts—Separating platinum from sands using bubbles
• Ask The Experts—Extraction of micro gold from black sands
• Ask The Experts—Difference between a Geiger counter and scintillator
• Then and Now: Is Gold Really Money?
• Gold, Quartz & Chalcedony—Part I
• Prospecting Australia—Part I
• Oregon Dredge Permit Litigation Update
• Gold From Black Sand Tailings
• The Fine Art of Panning Heavy Sands
• California State Gold Panning Championships
• An Expensive Lesson
• Judge Denies Request To Delay Michigan Mine
• Melman on Gold & Silver
