Prospecting witha black light

Bejay

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Mar 10, 2014
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Central Oregon Coast
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My grandfather was a desert prospector and he spent a lot of time out in the desert looking for highly mineralized zones.
During the day it is easy to walk past areas that have extreme mineralization. He knew that high mineralized fluorescent zones were associated with other minerals of value.

So in 1950 he invested in a prospectors black light. It had a battery pack that fastened to his belt and it powered a hand held "wand" powerful black light. I own the unit to this day...unfortunately I broke the lens and have to have one custom made....but the Southern Calif company who made it in 1950 is now in Seattle Wash.

My grandfather would venture out into the desert at night seeking to find fluorescent minerals. He would carry marker sticks and labeled bags in which he could place samples. When he found a fluorescent area he would post it with a stake/flag pole and place samples in his bag. He could visit the area again during the day.

Such fluorescent areas are NOT noticed during the daytime. The samples always varied and I'll post a link to help visualize what one can see at night prospecting with the right black light.
Fluorescent Minerals and Rocks: They Glow under UV Light!

Additionally along the Columbia river in Oregon one could go out at night and use the black light on the dredge spoils and find valuable gems. It was thought that pirate ships trying to escape the law would toss trunks of heavies into the river to relieve ballast and outrun the law (ships). Not sure on the validity of the speculation but I did see highly prized gems that were found by a neighbor man...as I was just a youngin at the time.


Bejay
 

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Interesting. I know in northern Nevada there are a few florescent areas that are fun to hunt. For some specimens. Happy hunting.:happysmiley:
 

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"Practical Uses of Fluorescence in Minerals"

"Fluorescence has some practical uses in mining, gemology, petrology and mineralogy. The mineral scheelite, an ore of tungsten, typically has a bright blue fluorescence. Geologists prospecting for scheelite sometimes go out at night with fluorescent lamps to look for deposits. They also use fluorescent lamps to examine core specimens and well cuttings. These exploration procedures have also been used for other minerals.

Fluorescent lamps can be used in underground mines to identify and trace ore-bearing rocks. They have also been used on picking lines to quickly spot valuable pieces of ore and separate them from waste. Many gemstones are sometimes fluorescent including: ruby, kunzite, diamond and opal. This property can sometimes be used to spot small stones in sediment or crushed ore. It can also be a way to associate stones with a mining locality."

I recall as just a young boy my grandfather searching for a major tungsten deposits.

Bejay
 

I've know guys that have done that, searching for scheelite near Randsburg. Find the tungsten and you're usually in the gold
 

Another handy fact on using a blacklight is that only about 10% of florescent samples will glow under long wavelength U.V. The long wave units are the ones used to light up posters etc. (Yes... even at 56 years old I've still got one. ;) ) So to get the most samples you'll need a short wave unit. Once you have both types, you can even find samples that will glow different colors under different wavelengths of U.V.

I was teaching our grand daughter about rocks and dug out the old long wave light and hooked it up to an extension cord and we started hunting out in the yard. We found a lot of samples (mostly Calcite) but were limited by the reach of the cord and the fact that it was a long wave unit. Still... She thought it was really cool. What really surprised her was when we'd come across a scorpion. A lot of folks don't know that they' glow a really bright green when hit with U.V. We did a good job of lowering the scorpion population that night.

I plan on picking up one of the duplex units that has both long and short wave lights/filters for field work in the near future. Not only can we use it for prospecting, but some samples can be worth a few bucks on the side.

SAFETY NAZI TIME: One thing not mentioned here is that short wave U.V. can be dangerous to skin and eyes! Proper safety goggles and keeping your skin covered while using shortwave U.V. can save your eyes and prevent skin cancer. Short wave U.V. is the wavelength that causes sunburn in natural light. NEVER look at a short wave U.V. source and never shine it in your pets eyes.Remember to stay safe and stay healthy.
 

GI Have you ever lit up a sidewinder? Those pissed off SOBs will fluorece also.
 

scorpion-glow.jpg
 

GI Have you ever lit up a sidewinder? Those pissed off SOBs will fluorece also.

As a general rule I don't play with Mr. Buzztail after dark no matter which species it happens to be. Now is it just sidewinders (aka Horned Rattler) or does this apply to all of them? Only ones I've seen out here so far have been the Banded Tail rattlers.
 

The only ones that I know of are the sidewinders. I don't think the More Harvey Green does or Timber rattler either. I know if the sidewinders had shoulders they'd have a chip on 'em. G/L
 

Yeah... The "Moes" have an attitude for sure! A good 12GA will knock that chip off (as well as everything else) real quick though. I've had to deal with poisonous snakes all over the world through the years and the Moes are in the top five for bad attitude.

Getting back to the topic here.... I've been looking at different units for U.V. prospecting and there are some nice ones out there. I want to pick up a dual wavelength one that is re-chargeable in the field without a lot of hassles. I don't want to have to keep feeding it batteries all the time as that gets expensive.

If you go to FeeBay and look at the fluorescent samples for sale there you'd be surprised at how small most of them are for the prices they're asking. We found one rock in the yard here that would easily make up a couple of dozen of their samples. I'm also going to talk to my mining neighbor and see if he'd allow me to check out some of the audits on his claim so I can get a better idea of what's below the surface in that area. It's nice having a lode mine as a neighbor! They've got like five different digs going on in different areas of their claim but I'm NOT going to go into the drift tunnel(s). I'll stick to the ones with proper bracing thank you very much! I don't know who did those drifts, but that has got to be the hardest type of lode mining out there! Hands and knees all the way. YUCK! Make my back ache just thinking about them.
 

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