History & Geology
Gold Depositiion and Gradients of Placer Streams—Part II
July 2012 by Jim Halloran
The steeper the gradient is, the more potential erosive power to move gold and other bedload sediments, and the more power to remove obstacles to flow.
Enrichment of Mineral Deposits by Weathering—Part II
While both zinc and lead deposits also are enriched by the surface weathering process, in part two we will look at the enrichment process for copper and also gold deposits, and at the interpretation of leached outcrops to figure how rich the concentrated deposits below them may be.
The Wild Rush To Find More Cobalt—Part II
In this second part on cobalt, I will take a look at the various types of cobalt deposits and how you can prospect for them. Who knows—perhaps the next big cobalt strike will be yours.
Calcite and Limestone
The other distinguishing feature of calcite has to do with its chemistry. Geologists sometimes take a small bottle of dilute hydrochloric acid out into the field with them because calcite reacts with acids to make a bubbly foam.
Nevada's Silver City Gold District -- Part II
May 2016...this district has had a continuous life of gold mining and milling that spans 150 plus years, and it appears that it will keep pressing on for many more years of production.
Rock and Formations of the Mother Lode Gold Belt
The faulting, folding and shearing that occurred in the Mother Lode belt has created zones of structurally weak rocks or contacts between different types of rock, which has been favorable for the deposition of gold bearing ores.
The Oquirrh Mountains, Utah
...we will visit three dormant mining districts that lie in the Oquirrh Range in Utah. Some major activity that transformed the lives of thousands of people occurred here from the mid 1860s to the late 1990s.
All the Gold Ever Mined...
If you have been prospecting for any length of time, then you have probably heard something like, “All the gold ever mined would equal a cube 60 feet on each side.”
Subscription Required:
The Bawl Mill
• The Life of an Independent Prospector
• Gold in Guyana—Part I: Porknocking on the Puruni River Road
• That Something Extra
• Prospecting for Copper Ores—Part II
• Metallic Trash—Scourge of the Prospector
• Gold Mining Boom in the Carolinas
• California Suction Dredging Update
• Mine, Baby, Mine!
• Hecla to Reopen Lucky Friday Mine
• Nova Scotia Shows It's Serious About Jobs & Mining
• Melman on Gold & Silver
• Mining Stock Quotes and Mineral & Metal Prices
