History & Geology
Simple Rules of Gold Geology: Comparing Epithermal and Mesothermal Deposits
July 2017 by Chris Ralph
Geology is a science of general tendencies with frequent exceptions, not one of hard and fast rules that are always true and never vary. For almost every well-accepted rule of gold deposits, I can point you to a number of important exceptions.
Prospecting for Silver Deposits
In some ways, silver is the forgotten precious metal because it straddles both the world of precious metals and jewelry, while having many important industrial applications like a base metal. The price of silver reflects both the precious metal investment demand as well as the industrial demand.
Placer Gold Deposits of Utah
The placer deposits of Utah occur in two distinct types of environments. These are 1) placers found adjacent to, and derived from, gold, silver and base-metal deposits; and 2) placers found in major rivers and derived from unknown, distant sources.
The Strange History of the Utica Mine
In the summer of 1854, John Selkirk, a discouraged placer miner who was down on his luck and ready to go back to Massachusetts, tied his mule up in a gulch north of what is now downtown Angel's Camp.
All the Gold Ever Mined...
If you have been prospecting for any length of time, then you have probably heard something like, “All the gold ever mined would equal a cube 60 feet on each side.”
The Goldfield Mining District, Nevada—Part I
An example of some of this extraordinary ore was a lot of about four tons from the Florence mine during the last days of a lease that averaged over 300 ounces of gold per ton.
Detector Brings New Life to An Old Lode Mine
…it was immediately evident the previous owner had not been using a detector. During just a few months of working the dumps part-time, he recovered gold in quartz specimens valued in excess of $40,000.
Benches and Fossil Placers
Unfortunately for us mortal humans, we have a poor perspective on geologic time. When we look at a landscape such as a stream valley, we see it only in two, or at the most, three dimensions. We have poor comprehension of the valley’s fourth and most important dimension—time.
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