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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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MMAC Update
March 2017
This will provide the opportunity to meet with many of the members of Congress in a more informal setting at several meetings, luncheons and dinners. And we have been offered the chance to meet with President Trump’s staff.
This will provide the opportunity to meet with many of the members of Congress in a more informal setting at several meetings, luncheons and dinners. And we have been offered the chance to meet with President Trump’s staff.
The Bawl Mill
December 2004
• Don't expect Santa to be healthy this Christmas
• Fast-food delivery
• Just in time for the holidays
• Don't expect Santa to be healthy this Christmas
• Fast-food delivery
• Just in time for the holidays
Environmentalists Target Pebble Mine
February 2007
Environmentalists are attempting to turn the jewelry industry against Alaska’s Pebble Mine before the project even gets fully under way.
Environmentalists are attempting to turn the jewelry industry against Alaska’s Pebble Mine before the project even gets fully under way.
The Bawl Mill
December 2007
• Reporting on Reports
• Answer the questions or we'll be forced to really bother you for a little while
• Some especially well-preserved mobile homes...
• Reporting on Reports
• Answer the questions or we'll be forced to really bother you for a little while
• Some especially well-preserved mobile homes...
How to Become a More Successful Nugget Detectorist—And Basic Information on Machines
November 2001
The intention of this article is to summarize the highlights of the past 25 years which have led up to metal detecting for gold nuggets and to cover some basic information...
The intention of this article is to summarize the highlights of the past 25 years which have led up to metal detecting for gold nuggets and to cover some basic information...
New Research Tool for Miners in Wyoming
September 2018
The Wyoming Geological Survey released an online interactive map...
Hardrock in Downieville
November 2000
A recent weekend trip found us leaving the Grass Valley, California area to meet up with some friends in Downieville.
A recent weekend trip found us leaving the Grass Valley, California area to meet up with some friends in Downieville.
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The Bawl Mill
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