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Mineralized Calderas in Colorado
May 2002 by Edgar B. Heylmun, PhD
A caldera is a large circular volcanic depression caused by collapse due to the removal of molten magma from an underlying magma chamber. The removal of magma is due to explosive venting of lava and pyroclastic material.
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Looking Back
March 1999
Excerpts from California Mining Journal, our original title, published 50 years ago this month.
Excerpts from California Mining Journal, our original title, published 50 years ago this month.
Mojave Desert Placer Mining
March 2002
Several locations in the Mojave Desert region of California have yielded placer gold, apparently scattered from nearby lode deposits that have long-since eroded from existence. Some of the areas are still popular with weekend prospectors, and some have been worked on a much larger scale in recent years.
Several locations in the Mojave Desert region of California have yielded placer gold, apparently scattered from nearby lode deposits that have long-since eroded from existence. Some of the areas are still popular with weekend prospectors, and some have been worked on a much larger scale in recent years.
Miner's Cabin—Red Shack Territory
June 2009
As we approached the river the view was outstanding and the sight was encouraging. A ravine coming down on the right side had been worked heavily, with rock piled back on each side. That surely meant there was gold somewhere close.
As we approached the river the view was outstanding and the sight was encouraging. A ravine coming down on the right side had been worked heavily, with rock piled back on each side. That surely meant there was gold somewhere close.
The Preacher of Sheeps**t Flats
September 2011
It seemed that the preacher always gave the same answer to anyone who asked where his gold had come from. His answer was, “If you know your gold, you can find it. However, you will have to find it the hard way, the way I found it.”
It seemed that the preacher always gave the same answer to anyone who asked where his gold had come from. His answer was, “If you know your gold, you can find it. However, you will have to find it the hard way, the way I found it.”
Investors Take a Shine to Platinum, Palladium
May 2010
Move over gold and make way for platinum and palladium. Investors are taking a shine to these lesser-known precious metals as their prices rise.
Move over gold and make way for platinum and palladium. Investors are taking a shine to these lesser-known precious metals as their prices rise.
Gondwana Gold Gravels
June 2000
The German scientist, Alfred Wegener, came out with his theory of "continental drift" in 1912. He was considered a crackpot and it was half a century before geologists and planetary scientists began to take a second look at his theory.
The German scientist, Alfred Wegener, came out with his theory of "continental drift" in 1912. He was considered a crackpot and it was half a century before geologists and planetary scientists began to take a second look at his theory.
Melman on Gold & Silver
February 2011
I hope long-term readers would agree that while your columnist does occasionally carry some arguments to an extreme length, I usually stay within the bounds of reason. I am pointing this out because I was struck by an economic vision a few days ago that could test those bounds.
I hope long-term readers would agree that while your columnist does occasionally carry some arguments to an extreme length, I usually stay within the bounds of reason. I am pointing this out because I was struck by an economic vision a few days ago that could test those bounds.
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