All Articles
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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Border Silver
January 2003
There is a sizable area that straddles the U.S.-Mexico border where native silver occurs in shear zones at relatively shallow depths. The district is in the low but rugged Pajarito Mountains, the highest point of which is 5,838 feet at Cerro Ruido, on the Mexican side. The deceptively rough terrain forced the first border surveyors, in 1855, to kill several mules and horses because of their injuries.
There is a sizable area that straddles the U.S.-Mexico border where native silver occurs in shear zones at relatively shallow depths. The district is in the low but rugged Pajarito Mountains, the highest point of which is 5,838 feet at Cerro Ruido, on the Mexican side. The deceptively rough terrain forced the first border surveyors, in 1855, to kill several mules and horses because of their injuries.
Small-Scale Mining with a Dozer and Detectors
December 2007
Even the best of metal detectors are only capable of seeing a certain distance down into the sand, gravel and rock of a placer deposit. Once all the gold that can be reasonably seen by a metal detector has been harvested, it can be difficult to...
Even the best of metal detectors are only capable of seeing a certain distance down into the sand, gravel and rock of a placer deposit. Once all the gold that can be reasonably seen by a metal detector has been harvested, it can be difficult to...
Gold, Quartz & Chalcedony—Part I
October 2011
Gold has always been noted to have an affinity for quartz to such a degree prospectors almost always dig on quartz veins in a search for the precious metal.
Gold has always been noted to have an affinity for quartz to such a degree prospectors almost always dig on quartz veins in a search for the precious metal.
Legislative and Regulatory Update
January 2014
• Pacific Legal Foundation joins effort to overturn California dredging moratorium
• PLP fund drive continues
• Pacific Legal Foundation joins effort to overturn California dredging moratorium
• PLP fund drive continues
Mining Stock Quotes and Mineral & Metal Prices
January 2014
Update on the West Mojave Desert Planning Area
August 2001
It is our hope that the following information will help desert residents understand what is happening and prepare them with adequate knowledge and information to participate in the government process as allowed by the United States Constitution and provided for in public law.
It is our hope that the following information will help desert residents understand what is happening and prepare them with adequate knowledge and information to participate in the government process as allowed by the United States Constitution and provided for in public law.
Gold Fever
August 1999
"Little Boys who pick up rocks either go to prison or become geologists."
"Little Boys who pick up rocks either go to prison or become geologists."
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The Bawl Mill
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• Looking Back
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