History & Geology
Gold, Quartz & Chalcedony—Part II
November 2011 by W. Dan Hausel
The specific gravity of chalcedony is 2.58 to 2.64. This is slightly lower than coarsely crystalline quartz because of slight porosity in chalcedony. Being so light, it will easily wash out of a gold pan.
Large Gold Deposit Types
It is not necessary to have a PhD in geology, but you need to know the basics, so that’s what I am going to try to dig into here—the understandable basics of these gigantic gold deposits.
Mohave County, Arizona: The Oatman/San Francisco Mining District
The Oatman/San Francisco Mining District’s historic gold production of 2.2 million ounces of gold since the 1880s makes this area Arizona’s greatest primary gold producing district.
The Gold, Silver and Base Metal Mines of Eureka, Nevada
...the area around Eureka, Nevada is well mineralized and seems to have a bright potential for future production of all sorts of metals.
Alaska's Cripple Creek Mining District
If developed with metal detecting in mind, this virgin ground could be a bonanza for nugget hunting.
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.
All About Quartz—Part I
One of the first minerals most prospectors learn to recognize is quartz, because, in the right circumstances, it can be an excellent indicator mineral for prospectors. Quartz is common, easy to identify, and is often associated with gold and other valuable metal deposits.
Placer Gold Deposits of New Mexico
While a large number of locations have yielded some placer gold, most of the state’s placer production has come from a few productive districts.
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The Bawl Mill
• Legislative And Regulatory Update
• Ask The Experts—Compensation for closed mining claim?
• Ask The Experts—Inconsistent fire assays
• Gold From Cemented Gravels
• Evolution Of A Gold Prospect
• Alaska to Target Rare-Earths
• Minnesota Delays Decision on Mineral Leases
• Alaska's Cripple Creek Mining District
• The Gold Of Horseshoe Bend
• Tyrie's Roadway Nugget
• Melman on Gold & Silver
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Are Permits Needed For Highbanking In California?
• Prospecting Australia—Part II: There and Back Again
