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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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Gold Near Boulder, Colorado
July 1999
Several mining districts near Boulder, Colorado mark the northeast end of the 240-mile-Iong Colorado Mineral Belt, which cuts diagonally across the Rocky Mountains.
Several mining districts near Boulder, Colorado mark the northeast end of the 240-mile-Iong Colorado Mineral Belt, which cuts diagonally across the Rocky Mountains.
Legislative and Regulatory Update
December 2012
• Increase in claim fees
• Impact of recent elections
• Current suction gold dredging status in California
• Parks in Southern California
• Increase in claim fees
• Impact of recent elections
• Current suction gold dredging status in California
• Parks in Southern California
From the Editor
May 2003
An article entitled “BLM Swindles War Hero Out of Gold Mine,” authored by Robert Boatman, appeared in our September 2002 issue. The Bureau of Land Management (BLM) was unable to provide comment on the article at the time.
An article entitled “BLM Swindles War Hero Out of Gold Mine,” authored by Robert Boatman, appeared in our September 2002 issue. The Bureau of Land Management (BLM) was unable to provide comment on the article at the time.
A Working Arrastra
April 2004
If everything you see, the men, the animals, the crude mechanism that grinds gold from rock, everything around you, looks to be from centuries ago, if the mysterious sound you hear is pure history and the smell around you is primitive, if the earth beneath your feet quivers with untold strangeness; and, the taste in your mouth sweeps time out of mind then, if all of this happens at once, if every one of your five senses has taken you into the past, then you’ve traveled back in time.
If everything you see, the men, the animals, the crude mechanism that grinds gold from rock, everything around you, looks to be from centuries ago, if the mysterious sound you hear is pure history and the smell around you is primitive, if the earth beneath your feet quivers with untold strangeness; and, the taste in your mouth sweeps time out of mind then, if all of this happens at once, if every one of your five senses has taken you into the past, then you’ve traveled back in time.
Legacy of the Wandering Jew Mine
February 2001
The Tyndall Mining District of Santa Cruz County contains the oldest mines in the state of Arizona. Described as the most celebrated mineral region in North America, its ancient mines have produced a phenomenal amount of rich masses of pure native silver and ore prior to the arrival of the early Spaniards extending into the present century.
The Tyndall Mining District of Santa Cruz County contains the oldest mines in the state of Arizona. Described as the most celebrated mineral region in North America, its ancient mines have produced a phenomenal amount of rich masses of pure native silver and ore prior to the arrival of the early Spaniards extending into the present century.
Legislative and Regulatory Update
January 2020
- PLF files petition with US Supreme Court on behalf of Oregon miners
- Land and Water Conservation Fund abuse by Forest Service
- Army asks for REE proposals
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The Bawl Mill
• Our Readers Say
• California Wilderness Coalition and The Nature Conservancy Recruit Government Employees to Carry Out Huge Land Grab
• Drywashing Rules Clarified
• The Keystone Gold-Copper District, Medicine Bow Mountains, Southeastern Wyoming
• Picks & Pans: Mining Tungsten Ore—A Case History
• Gold in Oregon
• Aussie Gold—A Look at the Northern Territory
• The Phoenix Gold Mine: A Brief History
• Calico Mine
• Mining Stock Quotes and Mineral & Metal Prices
• Looking Back
• Melman on Gold & Silver
