Proper Assaying of Placer Samples
November 2012 by Jim HalloranThe whole purpose of sampling mineralized ground is to measure the values in a small volume of material that would be representative of a much larger volume of similar material. The key word is representative. Chemical and fire assaying will not accurately represent placer deposits by themselves.
The first location we worked was a small, dry ravine cutting through many mineralized zones in an area where some hard rock mining had taken place in the past.
The burning question I needed answered was why didn’t the deposit ever get mined of at least one of the valuable minerals? A couple of reasons have come to light.
The very first thing to find out...is if the detector has the ability to be ground balanced.
Fortunately, there are products on the market that can address these problems and make a small-scale mining operation feasible.
These three simple upgrades, when taken together, will considerably increase a pocket plunger’s magnetic pull and make it less susceptible to breakage.
The signal I was hearing was coming from a vertical bedrock crack on the bank of the creek. I removed my backpack, took out my crevicing tools and started to clean out the crack when I saw a glint of gold.
I looked over and saw Ben on his knees, digging at the edge of the Manzanitas, almost underneath them. I thought back to the previous weekend when we were planning this trip—that day had been a “Ben day.”
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