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.
Alaska: Kodiak Islands Mineral Resources
The fresh material is worked and concentrated by the waves on the flat, wide beach platform. The waves wash away the lighter minerals, leaving the heavies near the bluffs and in depressions on the beach.Why Did This Silver Mine Close? - Pt III
Narrowing down a closure date will allow you to check the commodity price during that time and possibly confirm that a low price, rather than a lack of ore, was the driving force that closed the operation.
California: The Land of Big Nuggets—Part II
There are a number of Tertiary river channels in the area, most of which trend south-southwest. They tend to be steep, narrow, and rich with coarse gold.
Alluvial Paystreaks
The gravels in contact with the bedrock or false bedrock base are often the richest. The same facts apply to the alluvial paystreaks that are formed on gravel bars; the lowest level of the gold-bearing gravel is normally the richest.
Placer Gold Deposits of Utah
The placer deposits of Utah occur in two distinct types of environments. These are 1) placers found adjacent to, and derived from, gold, silver and base-metal deposits; and 2) placers found in major rivers and derived from unknown, distant sources.
Arizona's Vulture Gold Mine and Lost Dutchman
When prospectors and treasure hunters talk of gold in Arizona, it is the Lost Dutchman or Vulture mine they usually think of. The Lost Dutchman gold mine is just that—a myth chalked full of holes that has been embellished over time as any good legend should be.
Nevada's Lithium Boom
When prospecting for lithium, after confirming for macro attributes through research and field work, including examination of surface geology, the main tool is an accurate lithium assay.
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