How to determine if there is mercury in a lot.

[autumnwillow]

I have a customer who has a customer selling gold flakes, they claim it was from 1970's gold panning.

How do I know that mercury is not present in the flakes before I melt it?

Any ideas on how I could build a simple, cheap and safe retort? I already have a condenser. The problem would be the cooking vessel.

 

[butcher]

You can build a retort out of plumbing fittings fairly easy, the condenser is normally just a pipe or tube with a sock on the end dipped into the water.

 

[autumnwillow]

You can build a retort out of plumbing fittings fairly easy, the condenser is normally just a pipe or tube with a sock on the end dipped into the water.

From steel pipes? Would this be any good?


Now how do I seal this pipes properly so they wont leak? Since I'll be using propane/oxy I cant seem to think of any sealant that will survive the heat.

And about the gold flakes, there's no hope in determining whether there are traces of mercury left not unless I have an XRF correct?

 

[Lino1406]

Why especially mercury?

 

[denim]

a customer who has a customer selling gold flakes, they claim it was from 1970's gold panning.

Something about this sounds a bit fishy to me. Beware of scams my friend. Hope I am wrong.

 

[kurtak]

How do I know that mercury is not present in the flakes before I melt it?

If you see "any" of the flakes that have silvery look to them that is likely mercury that has amalgamated with the gold

It's not uncommon for at least "some" placer gold to have mercury that has amalgamated (coated) with some of the gold

Normally it is "very little"

I recently bought 3 grams of placer "flakes" & there are maybe only 4 - 6 flakes that have mercury amalgam as a surface coating

Unless there is "a lot" of amalgam mixed in the gold I would not try to retort it - instead I would put the gold in a beaker - cover it with D-water & add a bit of nitric - the nitric will dissolve the mercury - once the mercury is dissolved you can then drop the mercury out as a hydroxide or a carbonate - or cement it out with copper - which can then be "properly" disposed of

Kurt

 

[butcher]

Note: on the retort only the sock touches water to keep it wet, the end of the discharge pipe does not go down into down into water, but sits just above the water with the sock tied on the end, the sock which is wet touches the water to keep it wet.

I agree with Kurt, for just a little mercury coating on a few flakes of placer gold, you can get by without distilling off the mercury, and deal with it in solutions.

 

[autumnwillow]

Why especially mercury?

I did not add mercury into it. It was claimed "gold panned from the 70's." I'm just assuming that mercury is in it and this is only the second time I'm buying gold in a flake form. Not that I'm really interested in buying gold right now as the price is too high and the demand is really low but I'd rather process it myself than somebody else who would just melt it.

Unless there is "a lot" of amalgam mixed in the gold I would not try to retort it - instead I would put the gold in a beaker - cover it with D-water & add a bit of nitric - the nitric will dissolve the mercury - once the mercury is dissolved you can then drop the mercury out as a hydroxide or a carbonate - or cement it out with copper - which can then be "properly" disposed of

Kurt

The lot is approximately 200gms. Would this be considered safe for nitric digestion? Or safer to just distill it for a long time then just melt it?

When digesting in nitric do I apply heat and just wash with water several times after?

Note: on the retort only the sock touches water to keep it wet, the end of the discharge pipe does not go down into down into water, but sits just above the water with the sock tied on the end, the sock which is wet touches the water to keep it wet.

Is there a point why the pipe does not touch the water? I understand the purpose of the sock to disperse the vapors but wouldn't submerging the pipe be better so as to further cool the vapor along the way?

 

[FrugalRefiner]

Is there a point why the pipe does not touch the water? I understand the purpose of the sock to disperse the vapors but wouldn't submerging the pipe be better so as to further cool the vapor along the way?

The sock is not there to disperse the vapors, but to keep them from being dispersed. They'll condense on the wet, cool sock and join the rest of the mercury in the water jar instead of being dispersed and poisoning you and the environment.

The reason to keep the pipe out of the water is to prevent any water from being sucked back into the retort if the heating is lost. Water being drawn back into the retort could cause a dangerous steam explosion.

Dave

 

[kurtak]

autumnwillow - don't have time to really post much this morning as I an actually heading out the door to go do some gold panning this morning so will try to post tomorrow

That said & for now - based on my experience with fine placer gold - there is likely so little mercury in the mix that retorting is not the best option where as nitric will get the job of cleaning the gold up done

Kurt

 

[galenrog]

Kurt, please let us know which creek out there near John Day, and how well you did.

Autumnwillow, if you do not see anything silver in color, you probably have no mercury. Since mercury vaporizers at room temperature, the 40-50 intervening years may have taken care of any surface contamination. Still, the advice with nitric acid is good advice.

Time for more coffee.

 

[kurtak]

Unless there is "a lot" of amalgam mixed in the gold I would not try to retort it - instead I would put the gold in a beaker - cover it with D-water & add a bit of nitric - the nitric will dissolve the mercury - once the mercury is dissolved you can then drop the mercury out as a hydroxide or a carbonate - or cement it out with copper - which can then be "properly" disposed of

Kurt

The lot is approximately 200gms. Would this be considered safe for nitric digestion? Or safer to just distill it for a long time then just melt it?

When digesting in nitric do I apply heat and just wash with water several times after?

First off - without actually looking at the gold it is hard to tell how much if any mercury there "may" be in the lot

However with that said based on my experience with this kind of small/fine placer gold the likely hood of the mercury being enough to be any real concern just is not a problem - more then likely it is so little that it wont properly retort - there is likely not enough for it to properly condense & roll out the end of the retort cooling tube

My experience; - in the late 70s early 80s when I lived in Northern California & knew & worked with people running 6 - 8 & 10 inch dredges so I saw "many" ozt. of fine flour/flake gold from their black sand clean ups

There was always evidence of "some" mercury coating on a "few" of the flakes - never did I see enough mercury in these fine gold clean ups for a retort to properly vaporize - condense & collect the mercury

In a 200 gram lot (which is about 6 ozt.) I would be surprised if there was a couple/few tenths of a gram of mercury - that's just not enough to collect & roll out the end of the retort tube --- This is of course with not actually seeing it

A nitric wash is the go to method for "cleaning up" this kind of gold

If it were me - I would make up a wash of 2/3 D-water & 1/3 of 70% nitric & use enough wash to cover the gold in a beaker - no heat needed - stir the gold with a glass rod from time to time till you see no more silver coating on the flakes - decant the wash & wash with D-water till all the acid is washed out of the gold (do not use tap water as that will create mercury chloride) --- treat the nitric wash(s) to Ph 7 with baking soda - this will precipitate the mercury as mercury bicarbonate - filter out the bicarbonate & dispose of it (the filter) according to local regulations --- most landfills provide taking hazardous waste for little or nothing

That is what I would do

Kurt

 

[kurtak]

Kurt, please let us know which creek out there near John Day

:lol: :lol: :lol:

Thats like asking me where my favorite mushroom &/or deer/elk hunting spot &/or favorite fishing hole is :shock: :twisted:

I will go as far as to say it was not to far from Greenhorn

Right now I am going up with just a pan & shovel prospecting on different creeks to determine the best place to file on claims that may have lapsed & open to file on (a lot of claims have lapsed in the last couple years)

so far found two location worth taking a sluice box into one of which was yesterday which was also the better of the two - four other locations were duds - this was my third week end out

At least thats all I am going to say on the "open" forum :mrgreen:

Kurt

 

[autumnwillow]

Got it! Thanks everyone!
I'll let you guys know what happened if the deal pushes thru not unless I die from it. :lol:

 

[galenrog]

I will go as far as to say it was not to far from Greenhorn

Good area. The likelihood of finding a creek, wash, or gully near Greenhorn that does not have gold is low. The questions are quantity and availability for claim. A few areas near there may present the same issue Autumnwillow brought up at the beginning of this thread, so do not throw out any heavies that are grey or silver in color.

 

[philddreamer]

galenrog wrote:

Good area. The likelihood of finding a creek, wash, or gully near Greenhorn that does not have gold is low. The questions are quantity and availability for claim. A few areas near there may present the same issue Autumnwillow brought up at the beginning of this thread, so do not throw out any heavies that are grey or silver in color.
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _

WHAT!?

No more time for coffee!?!?!? :mrgreen:

 

[galenrog]

Had it in hand. Wife brought home a hazelnut latte from Dutch Bros.

 

[autumnwillow]

Deal didn't push thru! Customer did not come back. No :G bar for me.