Small Mine Selective Blasting
January 2000 by Dr. Ralph E. PrayDrill holes in a mineralized vein often penetrate hidden layers of poor ore which, after blasting, end up diluting the production quality. Disseminated gold ores carrying two ounces per ton may be identical in appearance to adjacent vein material...
I have figured out over the years that the winning combination is hard work, persistence, knowledge, and a little luck. This leads me to describe one of my best finds ever, a “honey hole” of placer gold, if you will.
A series of coastal ranges, separated by narrow valleys, characterize coastal California south of Monterey. The mountains rise to 5,800 feet in elevation, with annual rainfall varying from 12 to 64 inches, depending on elevation and exposure.
Common thought is the switchback slows the velocity of the rushing water and gold drops out from the cut bank to a fill gravel bar within or below the switchback. I am not going to disregard that model; however, I hope to improve upon it.
• Are these gold amounts large enough to interest a mining company?
Excerpts from California Mining Journal, our original title, published 50 years ago this month.
Over fifty pieces of dendritic gold, ranging from 1 gram up to 2.5 ounces, were recently discovered at a mine in the Allegheny Mining District in Northern California.
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