***************************************
OH Yesssssss - The Old "Thermal Shock" idea.
Having heard for years about that technique (to be used on "Black Sands" but not pyrites) I once tried it.
The concept is to get Black Sands (Iron ores of Magnetite and Hematite) from after the final processing of concentrates and heat them to a high temperature. When hot, then pour them into cold water to shatter any exterior 'shell' and release """Encapsulated or Trapped Gold""".
Just to try out the technique, one bitterly cold winter 4 or 5 years ago, I had a roaring bed of coals in my big ol' woodstove and used special long handled tongs to carefully place a coffee can with 3 or 4 handfuls of previously panned out (over and over) black sands into the hottest area of the stove.
After about an hour the concentrates and the can became very hot. OMG HOT!
While the concentrates were heating I drew cold water and put it outside, also, to get even colder. Then I went outside and gathered most of a 20 L bucket of snow which was kept outside to stay really, really cold.
After an hour the coffee can and it's contents were light yellow/red - very hot!
In came the snow and the tub into a large open area on the concrete floor by the wood stove. Into the tub went the water and the snow and everything was swirled around so the temp of the water was as cold as I could get it. Then with some floating snow on the water, with the glowing red can and it's contents in the tongs I stood facing the tub of very cold water and, in a circular motion, poured all the concentrates straight into the center of the water.
.
.
Damnedest thing you ever saw!
.
.
One loud awful screaming, snarling sound as the first of the red hot sand started to hit the water. Then a roar. Not a gentle sizzle, not a pop - rather a deep hoarse moan. Have you ever heated a steel rod bright red and thrust it into water? 50 times that.
Instant steam flying straight up into the air. Wet black sand flying up and billowing with that steam. Sandy grit and water cascading everywhere within 3 meters of the large tub. Clouds of steam everywhere. Painted concrete floor covered with steaming water and sand. I was covered in steaming water and sand. The only place I didn't get sand was my eyes - against prior conditioning I had worn gloves and goggles.
Thank God my wife was away for a few hours. She never knew.
When "things" calmed down I recovered the "Thermally Shocked" sands from the floor and the tub and painstakingly panned them out again -- multiple times.
Guess what I found? ONE minus 50 speck of Gold.
Will I Ever do that again?
NO!
OH, Heavens, NO!
NO.
NO!
Now, would I recommend that you do that? Well, maybe, but only if you set up the camera and video tape the entire adventure -- and -- post it here on the forum.
Otherwise, just put the kettle on and just have a cupp'a instead.
Bottom line - the only Gold you will find will be the Gold that got past you while panning. The only "Thermal Shock" will be to your nervous system.
Joe
