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Author Topic: Gold separation in swirling water  (Read 5757 times)

Offline Sam McCord

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Gold separation in swirling water
« on: 12/10/2011 19:10:34 »
I am an amateur prospector. Recently I viewed two videos on separating gold from sand and black sand and other heavy minerals. In a nut shell, one had a gold pan on a flat surface with about 2 inches of water. He pushed all the material to the outer edge of the bottom of the pan and started to stir the water slowly clockwise. As he was stirring he would move the stirring finger closer to the center. As this was done, the lighter material would slowly move to the center leaving the gold particles at the outer edge. This had to be done several times, but eventually all of lighter material was in a small pile in the middle of the pan and the gold was at the edge. The other video showed a guy with a couple of 5 gal buckets. They would be nested inside each other. The upper bucket had a 2'' hole in the center bottom, which had a pipe cap in it, creating a small cup if you will in the bottom of the bucket. The upper bucket would be filled with water too within about 3 inches of the top. He would take a stout stick and start to stir the water quite swiftly and then pour the gold bearing sand in the water. He would pour the sand in near the bucket side walls. He would then stir more and let it settle some. Then he would use the stick to push the material around on the bottom and start to stir again very rapidly. This carried on for about 3 to 4 cycles of mixing and stirring. Ultimately, he would reach into the upper bucket and pull up the pipe cap, which is full of material, allowing all the water to drain into the lower bucket. The claim is that if there is any gold in this sand it will all be in this cap. He offers the challenge that if anyone doesn't believe it, to just re-do the process with the material left over and see if there is any gold that was missed. These two processes seem to contradict one another. One is  moving the gold to the center as in the bucket video and the other leaves the gold at the edges and moves the lighter material to the center as in the finger stirring in the gold pan method. The obvious difference is the speed the water is moving and the amount of material being worked. I would have thought the physics would be the same though. I am interested in why these work as they do. What are the physics at play here? Here are links to the two videos. Hopefully you can see them.


This is the gold pan video:   http://www.golddredgervideo.com/guest/poppan.wmv


This is the bucket video: 

Thank you for any info

Craig


 

Offline Geezer

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Gold separation in swirling water
« Reply #1 on: 12/10/2011 22:39:23 »
Are you THE Sam McCord? (The one that was played by John Wayne.)
 

Offline Sam McCord

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Gold separation in swirling water
« Reply #2 on: 12/10/2011 23:43:49 »
If there was such a guy, he would be tougher than I. I liked the movie North to Alaska and I like John Wayne, but no, I am not either one. Just a middle aged guy in Colorado crushing quartz and panning it out with hope of seeing some gold. Thank you for reading my post... take care.

Craig
 

Offline Geezer

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Gold separation in swirling water
« Reply #3 on: 12/10/2011 23:56:50 »
Ah! Shame really, but it's a great handle.

I should warn you that, how should I put it, most   nearly everyone else  some of the people on this forum are probably criminally insane slightly bonkers, so take everything they tell you with several large shots a grain or two of salt.
 

Offline RD

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Gold separation in swirling water
« Reply #4 on: 13/10/2011 03:27:23 »
This is the bucket video: 

The two buckets could be functioning like a hydrocyclone ...

Quote
hydrocyclones are used extensively both to classify particles for recirculation in grinding circuits and to differentiate between the economic mineral and gangue.
http://en.wikipedia.org/wiki/Hydrocyclone

The apparent contradiction of the two methods may be due to the gold particles being of different sizes in either case, e.g. the bucket method working only for tiny "nano" gold particles, the pan method only for bigger grains of gold.
« Last Edit: 13/10/2011 06:19:05 by RD »
 

Offline Sam McCord

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Gold separation in swirling water
« Reply #5 on: 13/10/2011 17:23:24 »
Hello Geezer,

Thank you for the info. I will keep it in mind. You take care out there...


Craig
 

Offline Sam McCord

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Gold separation in swirling water
« Reply #6 on: 13/10/2011 17:27:07 »
Hello RD,

Thank you for the hydrocyclone info. I will look into this and see if I can understand the physics, as to why it works the way it does. Take care....


Craig 
 

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Gold separation in swirling water
« Reply #6 on: 13/10/2011 17:27:07 »

 

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