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.
My partner had the contacts and it wasn’t long before we had an agreement in place and the company had a geologist on site. I recall a time when he was getting the lay of the land, so to speak, and he broke off a rock sample and inspected it with his magnifier.
Epithermal deposits form in the ground at shallow depths. They are popular with prospectors because can yield very rich deposits and they are widespread in the Western US.
Plumas County has a rich heritage of gold mining, much of it from placer deposits that can still be searched and panned today. Being at the far northern end of California’s famed Mother Lode, it is quite often overlooked by those searching for gold today—really a well-kept secret after all of these years!
The placer mineral identification key is designed to answer this question. It attempts to recognize all the minerals in your gold pan concentrates.
There are literally thousands of abandoned wasterock and ore dumps that dot the United States that could hold many tones of strategic metals.
While both zinc and lead deposits also are enriched by the surface weathering process, in part two we will look at the enrichment process for copper and also gold deposits, and at the interpretation of leached outcrops to figure how rich the concentrated deposits below them may be.
From time to time I’ve been doing a series on critical metals and how important they are to our complex and technological society. This month we are going to take a look at copper, and how important that metal is to our modern lives.
The Bawl Mill • Ask The Experts: What is a Spanish needle? • Ask The Experts: Sulfides and fluxes • Legislative and Regulatory Update • The "Madonna Nugget"—A Weekend Hunt to Remember • The Goldfield Mining District, Nevada—Part II • Sunset Sunbaker • A Prospecting Adventure in Mexico • Critical Minerals: Tungsten • Police Urge Author to End Treasure Hunt • Melman on Gold & Silver • Mining Stock Quotes and Mineral & Metal Prices