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.
All About Pyrite
Most prospectors learn early that pyrite is fool's gold...but the truth is it can be an excellent indicator mineral for gold and in many cases does contain small amounts of gold.
Enrichment of Mineral Deposits by Weathering—Part I
The exact minerals formed in the concentrated supergene deposits depends much on the type of country rock around the deposit and the chemistry of the deposit itself, but if conditions are right, this process will form some rich patches of bonanza ore, in some places valued at thousands of dollars to the ton.One Question, Forever Unanswered—Did He Really Find the Gold?
This was one of those stories where you have no doubt that the person telling it believes it to be true. But was it?
Eastern Arizona: Gold and Base Metal Deposits Part II
In this review of precious and base metal deposits in Arizona, it is apparent that several significant mines and mineral deposits occur in eastern Arizona, and there is considerable potential for new discoveries.
Benches and Fossil Placers
Unfortunately for us mortal humans, we have a poor perspective on geologic time. When we look at a landscape such as a stream valley, we see it only in two, or at the most, three dimensions. We have poor comprehension of the valley’s fourth and most important dimension—time.
The Wild Rush to Find More Cobalt—Part I
While some future cobalt will come from recycling lithium batteries and other products, the coming huge need for cobalt is virtually a perfect storm of heavy demand and insufficient supply.
Gold Deposition and Gradients of Placer Streams—Part I
When placer miners from the gold rush era began experimenting with the slope of their sluices, they must have pondered the ideal slope for trapping gold in a creek bed too. Logic suggests the same is true for streams...
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