History & Geology
All About Chalcopyrite
March 2017 by Chris Ralph
…there are loads of different copper minerals, but a large number of them form first in the ground as chalcopyrite and then through the effects of weathering are changed into other minerals like malachite, cuprite and chrysocolla.
The Miner’s Switchback
Common thought is the switchback slows the velocity of the rushing water and gold drops out from the cut bank to a fill gravel bar within or below the switchback. I am not going to disregard that model; however, I hope to improve upon it.
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.
Picks & Pans: Gold Recovery in Placer Mining Operations
Two of the major factors affecting the profitability of a placer mining enterprise are the relative efficiency of the mining equipment, and the rate and percentage of recovery obtained while conducting mining operations.
Gold of Plumas County
Plumas County has a rich heritage of gold mining, much of it from placer deposits that can still be searched and panned today. Being at the far northern end of California’s famed Mother Lode, it is quite often overlooked by those searching for gold today—really a well-kept secret after all of these years!
The Pearce Mineralized Area, Dragoon Mountains, Arizona—Part II
There are many prospects within the known mineralized area and along the margins of the mineralized area that should be examined for gold and silver.
Mass Wasting & Gold Deposits
Not all of these slides and debris flows will produce results, but if you search for these while prospecting in your gold producing areas, then you can increase your odds of finding new gold.
Testing Ores for Free Gold
I get a number of questions from people about testing and treating hard rock ores. The simplest way, but also an expensive one, is to just have an assay test done by an independent assay firm. As an alternative...
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