History & Geology
Eastern Arizona: Gold and Base Metal Deposits—Part I
February 2011 by W. Dan Hausel
Arizona is well-known for its copper-gold porphyries and massive base metal-gold sulfide deposits such that primary gold deposits in the state are often overshadowed.
How To Identify Minerals
There are a number of characteristics that are used when one identifies a mineral. Each characteristic gives an indication as to what the mineral might be, and the combination of them will point to what it is.
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.$50 Million in Gold From 1857 Shipwreck Approved for Sale
The gold is all for sale. Just one tiny coin alone could go for $1 million because of its combination of rarity and the history behind it...
Know Your District
We have to remember that the earliest miners were not geologists, but came from a variety of backgrounds. Their survival depended on finding enough gold so they worked hard and adapted to whatever challenges these new areas presented.
Epithermal Gold and Silver Deposits
Epithermal deposits form in the ground at shallow depths. They are popular with prospectors because can yield very rich deposits and they are widespread in the Western US.
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.
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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