History & Geology
Natural Gold Alloys
March 2014 by Chris Ralph
Natural gold is never 100% pure; all natural nuggets contain at least some impurities. We're going to take a look at just what some of those impurities might be.
Confluence Placers
Confluences of placer streams are well known as concentration sites for heavy minerals. The basic reason is that...
The Wisdom of Mark Twain—And Tales of Cheating the Unwary Prospector
I (enjoy) Twain’s description of a gold mine, “A hole in the ground with a liar at the top.” Some humor here? You bet, but I’m sure he meant it to be a real eye opener as well.
Simple Rules of Gold Geology: Comparing Epithermal and Mesothermal Deposits
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.
The Verde Copper-Gold-Silver-Zinc District, Jerome, Arizona
When I was a student in the College of Mines at the University of Utah, the Verde district was used as an exploration model for “submarine volcanogenic massive sulfide deposits.” So I looked forward to visiting this district and the town of Jerome in central Arizona in the spring of 2012.
Prospecting for Surface Flood Gold Placers on Low and Intermediate Gradient Streams
Sample panning is a very important method used to find the richest parts of a flood gold deposit before setting up equipment and running material.Critical Metals: Copper
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.
Ophir—Possibly the Best Kept Secret in Alaska!
...I decided to excavate the semi-frozen high-bank that was resting on a soft shale bedrock footing. Within three feet, I encountered an intrusive!
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The Bawl Mill
• Ask the Experts
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• Prospecting Hard Rock
• Reese River Silver Mining District, Nevada
• Twenty-Five Gold Indicators You Should Know
• Alaska: Large-Scale Mining Can Be Done Right
• Gold of the Iditarod Mining District, Alaska
• Bedrock
• Government Takes Land for Open Space
• Comments on Gold Rush and Bering Sea Gold Series
• Hidden Value in Old Tailings
• Melman on Gold & Silver
• Mining Stock Quotes and Mineral & Metal Prices
