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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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Legislative and Regulatory Update
June 2014
• Idaho miners will challenge new EPA permit at rally
• California proposes to amend definition of a suction dredge
• Proposed rule redefines "navigable waters"
• Idaho miners will challenge new EPA permit at rally
• California proposes to amend definition of a suction dredge
• Proposed rule redefines "navigable waters"
USGS Reports Increase of Imported Minerals
September 2001
Since 1993, US reliance on imports of raw and processed materials of mineral origin has increased more than seven fold.
Since 1993, US reliance on imports of raw and processed materials of mineral origin has increased more than seven fold.
Legislative and Regulatory Update
November 1999
Robert Sanregret—Attorney at Law
Western Mining Council
National Association of Mining Districts
Robert Sanregret—Attorney at Law
Western Mining Council
National Association of Mining Districts
Mining Stock Quotes and Mineral & Metal Prices
August 2013
From the Editor
September 2005
Thanks to the hard work of our writers and staff, along with the support of our advertisers, we are beginning our 75th year in print.
Thanks to the hard work of our writers and staff, along with the support of our advertisers, we are beginning our 75th year in print.
Tons of Gold Buried Under World Trade Center
October 2001
Some 11.8 metric tons of gold worth an estimated $110 million, and 30.2 million ounces of silver valued at $121 million, are buried in the rubble below one of the collapsed buildings in the World Trade Center, The New York Times report
Some 11.8 metric tons of gold worth an estimated $110 million, and 30.2 million ounces of silver valued at $121 million, are buried in the rubble below one of the collapsed buildings in the World Trade Center, The New York Times report
Lightning Creek, British Columbia
September 2000
Lightning Creek is one of the famous placer gold streams in the Cariboo district of east-central British Columbia, Canada. It is 445 miles, by highway, north of Vancouver, some 50 miles east of the town of Quesnel (pop. 8,500).
Lightning Creek is one of the famous placer gold streams in the Cariboo district of east-central British Columbia, Canada. It is 445 miles, by highway, north of Vancouver, some 50 miles east of the town of Quesnel (pop. 8,500).
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The Bawl Mill
• Our Readers Say
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• Drywashing Rules Clarified
• The Keystone Gold-Copper District, Medicine Bow Mountains, Southeastern Wyoming
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• The Phoenix Gold Mine: A Brief History
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• Mining Stock Quotes and Mineral & Metal Prices
• Looking Back
• Melman on Gold & Silver
