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.
Confluence Placers
Confluences of placer streams are well known as concentration sites for heavy minerals. The basic reason is that...
Conrey Dredge No. 4
The large buckets were favorable for the type of ground worked. The gravel was tenacious and compact, due to the existence of irregular pockets of clay.
Prospecting for Surface Flood Gold Placers on Low and Intermediate Gradient Streams
Sample panning is a very important method used to find the richest parts of a flood gold deposit before setting up equipment and running material.Liberty and the Phoenix Mine
Liberty, Washington is located in the mountains near Yakima and Ellensburg. There is nothing much in Liberty except for about 20 houses on patented mining claims and a lot of dry holes.
Natural Gold Alloys
Natural gold is never 100% pure; all natural nuggets contain at least some impurities. We're going to take a look at just what some of those impurities might be.
The Golden Days of Julian, California
Some scattered reports say that gold may have been washed from streams here as early as the 1840s, but the undisputed major discovery came in 1870.
The Goldfield Mining District, Nevada—Part I
An example of some of this extraordinary ore was a lot of about four tons from the Florence mine during the last days of a lease that averaged over 300 ounces of gold per ton.
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