Separate pyrites from gold

[Ben78]

I wouldn't ordinarily ask a question like this but its doing my head in...

I regard myself as 'up there' in panning skill, ie can empty my pan confident that I am not losing gold, can separate every last bit of black sand from the gold etc etc. I also have a blue bowl that I use for catching the super fines from the sluice when I don't want to pan it back.

I spent a few hours crushing some quartz over the weekend and got a lot of good colour, however it is mixed in with some pyrites that I just can't shift. The gold seems to move at the same rate as the pyrites. I classified to 50 mesh and put it in the blue bowl, turned it down super slow and it took 3 hours to process half a cup of cons - there was gold in the bucket along with pyrites.

Driving
Me
Nuts
...

Anyone got any ideas?

 

[Guest]

You probably would've but have you checked to see if it's magnetic or not?

 

[Guest]

I heard you can burn it off with sodium carbonate, May pay to research I have no idea of the dangers because I know pyrite gives of sulfur dioxide when burnt without the sodium carbonate. But i aint no chemist but may be a base for your research.

 

[Ben78]

You probably would've but have you checked to see if it's magnetic or not?

Not magnetic - Have to use a magnet to get the dolly pot chips out

 

[Ben78]

I heard you can burn it off with sodium carbonate, May pay to research I have no idea of the dangers because I know pyrite gives of sulfur dioxide when burnt without the sodium carbonate. But i aint no chemist but may be a base for your research.

Arsenopyrites was very common in this area, and is quite heavy at 6.1g/cm3 - certainly don't want to heat it up as it gives off fumes high in arsenic

Might have to bite the bullet and get some mercury for times like this.

 

[Guest]

Wowzers like i said i aint no chemist hahahaha.

 

[Heatho]

I think hydrochloric acid may dissolve Pyrite, but yeah arsenopyrite and HCL probably equals severely bad idea. If there is'nt too much then heating may not be too bad in a decent breeze.

 

[TenOunce Tone]

Tweezers and then tweezers or fine hypodermic and magnifing glass? put on gloves so you dont absorb through skin when or if you touch it...

 

[garnethawkins]

If you have access to nitric acid that will get it out without harming thegold, just be sure to wear a ventilation mask and do it out side as it releases sulphurous gas which if breathed in creates sulphuric acid in your lungs... NOT A GOOD WAY TO GO

 

[Redmanti]

You sure that's gold in the first place?

 

[Ben78]

You sure that's gold in the first place?

You think it's something else?

 

[Redmanti]

You sure that's gold in the first place?

You think it's something else?

Looks like Pyrite. But I'm no geologist.

After working a hard rock mining area for over 6 months (Pambula) where the gold is visible but mixed in with the rock extremely finely I came to the conclusion that's its too hard to work on. Lots of chemistry that isn't safe. Nowadays I just do alluvial and the gold behaves the way it should.

The old timers used cyanide ponds. Might be worth checking Trove http://trove.nla.gov.au to see how the old miners treated the same rocks at your location. Could find an answer there.