History & Geology
Epithermal Gold and Silver Deposits
April 2017 by Chris Ralph
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.
Critical Minerals: Titanium—Part II
There are both hard rock and beach sand types of titanium deposits, but the hard rock deposits need to be at least 10 percent titanium while the beach sands often are economic with only two or three percent titanium.
Montana’s Rosetta Stone: Discovering Mines In The Treasure State
This is the intelligent way to start modern prospecting. The value of literary research yields challenging outings, specimens, history and geologic research.
The Seven Troughs Mining District
The favorable geology of the northeastern and central parts of the Seven Troughs Range are the parts most interesting to prospectors. They are underlain by a thick sequence of Tertiary volcanic rocks, mostly rhyolites and andesites.
Picks & Pans: Gold Recovery in Placer Mining Operations
Two of the major factors affecting the profitability of a placer mining enterprise are the relative efficiency of the mining equipment, and the rate and percentage of recovery obtained while conducting mining operations.
Sulfides and Intergrain Gold Wire Nuggets
...these nuggets have not traveled far from the lode because the golden wire lattices would have been torn apart or flattened during weathering of rock and deposition by violent stream action.
Gemstones to Die For
Some gems can potentially poison you, make you sterile and even make you forget who you are.
The Significance of Nuggets in Placers
Chances are better that both types of gold did not come from the same source. Let's look at the probable conditions to cause two types of gold in a placer.
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• Ask The Experts: Is an XRF gun useful for prospecting and mineral identification?
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• Ask The Experts: Can a long range locator probe detect gold in quartz?
• Weathering, Erosion and Placers
• The PIGMI—a DIY Crevice Tool
• Diary of a Diamond Prospector
• The Ups and Downs of Nugget Hunting
• Melman on Gold & Silver
• Mining Stock Quotes and Mineral & Metal Prices
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