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Strategies & Market Trends : 2026 TeoTwawKi ... 2032 Darkest Interregnum -- Ignore unavailable to you. Want to Upgrade?


To: TobagoJack who wrote (94754)9/19/2012 3:57:04 PM
From: Snowshoe  Read Replies (1) | Respond to of 217574
 
>>Am now learning all about mine and mill security. The ways of stealing gold from a mill are truly ingenious.<<

There's an old trick called "high grading", where miners pocket the best ore and take it home. I once stood on the edge of this Glory Hole, where the boyz doomed themselves by shaving off too much ore from the support pillars...

Touring Arizona’s Vulture Gold Mine ghost town
stripedpot.com

Stand over the 1923 Glory Hole where seven miners and 12 burros met their death while high-grading. As they removed ore from the walls of the mine, it caused a massive collapse. According to Wikipedia, common in the United States in the late 19th century and early 20th century, high graders would usually conceal gold ore in a pocket or lunch pail, or within the body, and later attempt to fence it on the black market.

As mining companies became more aware of the growing problem, they built changing stations where they forced the miners to shower after their shift in the mines, making it easier to foil attempts at theft.




To: TobagoJack who wrote (94754)9/21/2012 12:34:58 AM
From: mach  Respond to of 217574
 
Seems like it would be fairly easy to distinguish between a gold plated tungsten bar vs pure gold by measuring the speed of sound in the bar (Au: 3240 m/s, W: 5180 m/s). You may be able to use a commercial handheld ultrasonic thickness gauge, e.g. advanced-ndt.co.uk

A new business opportunity for a instrument that would hold the common Au bar sizes and with the press of a button tell you if it's pure gold?

Mark