Washing Gold Powder Tutorial Question

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kernels

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Joined
Apr 14, 2016
Messages
672
Location
Auckland, New Zealand
Good morning from (windy today) New Zealand, I dropped my second batch of gold last night and it settled overnight, I've now come to the washing part and have a couple of questions

The tutorial includes the following steps:

5.Add just enough water to cover the gold powder and boil for 5 minutes (Removes undissolved and water soluble salts)
6.Let settle and pour or siphon off the water into the stock pot.
7.Repeat three times.
8.Add just enough muriatic acid to cover the gold powder.
9.Boil until the acid is no longer discolored by the process and pour or siphon off into the stock pot after testing with stannous. If gold is present keep in separate beaker to precipitate later.
10.Repeat the water rinse as above.

Question: For step 6, do you want to pour off the water while it is still very hot ? If you have to wait another few hours for any suspended gold to settle, won't the salts you dissolved with the hot water crystallize out again ?
 
kernels said:
5.Add just enough water to cover the gold powder and boil for 5 minutes (Removes undissolved and water soluble salts)
6.Let settle and pour or siphon off the water into the stock pot.
7.Repeat three times.

Question: For step 6, do you want to pour off the water while it is still very hot ? If you have to wait another few hours for any suspended gold to settle, won't the salts you dissolved with the hot water crystallize out again ?
Usually, once you've boiled it, the gold starts to agglomerate into larger clumps, so it settles faster. You can check for turbidity by shining a bright flashlight or laser through the solution. Once it's clear, you can decant or siphon. Any minor amount that may not have settled will settle out in your stock pot.

As the solution cools, some salts could crystalize out if the gold is really loaded with impurities, but you repeat the step until the solution is clear (maybe three times, maybe five. it depends on your situation). So any small amount that might crystalize out from the first wash will dissolve in subsequent washes.
 
Thank you Frugalrefiner, worked exactly as you indicated, once it had settled and 'clumped' once, it seems to stay clumped for the subsequent washes, too easy :)
 
I wouldn't boil it.

If you're going to do that, try with 60% sulfuric acid, which will send off the Cl part of AgCl as HCl and form well soluble AgSO4. Filter through polypropylene filter cloth
 
Hi

When we wash gold powders 3 times with water and 3 times with hcl , how much time we must wait for settleing gold powders? (I don't like transfer any gold to stock pot)

Thanks

FrugalRefiner said:
kernels said:
5.Add just enough water to cover the gold powder and boil for 5 minutes (Removes undissolved and water soluble salts)
6.Let settle and pour or siphon off the water into the stock pot.
7.Repeat three times.

Question: For step 6, do you want to pour off the water while it is still very hot ? If you have to wait another few hours for any suspended gold to settle, won't the salts you dissolved with the hot water crystallize out again ?
Usually, once you've boiled it, the gold starts to agglomerate into larger clumps, so it settles faster
Hi
How much time does it need to settle completely and ready to decant?
Thanks
 
I Know it depends to purtiy of gold powders but 10 or 15 minutes is enough for settleing?
 
The cleaner your drop, the faster it will settle. If you leave it to settle until completely clear, you introduce time for more metals to be drug down with your gold. Since the heavier stuff comes down quick, I sometimes will pour off the still cloudy, but mostly completely dropped, solution and leave it to settle out in another beaker. While waiting for other processes I will work on the cloudy solution that should have settled out by the next day, and attempt recovery of any residual gold then. Since a lot of what I work on belongs to me, I may wait until I have several of these secondary solutions sitting (in one beaker) until I have enough to make it worth the effort. If it belongs to someone else, I will work it as soon as it looks cleared up. Once I have cleaned up the secondary solution, I then add the solution to my stock pot. These finer and slower settling powders are often very dirty compared to what you will recover from the initial drop as well. Often times, in my case, the clean up often won't pay for what I recover and this is why I let them sit and add up. If it belongs to someone else, then I make extra efforts to give them back what is theirs, and make allowances for the extra efforts.

As for how long, it varies from batch to batch. I usually wait from 30 minutes to an hour, depending on the situation, and because I usually step over and spend a few minutes doing something else. I have seen a solution go beautifully clear in 10 minutes, usually after a second refine. I have waited 48 hours, and hated the wait. If it is to slow you could filter it, then reprocess it filter and all. Again, it comes down to your experience and hands on knowledge to make an informed decision at the time. I am still learning so, I expect mistakes as I go, but they are way fewer than I was making even a year ago. And nothing like I made when I first started.
 
saadat68 said:
Hi

When we wash gold powders 3 times with water and 3 times with hcl , how much time we must wait for settleing gold powders? (I don't like transfer any gold to stock pot)

Thanks

FrugalRefiner said:
kernels said:
5.Add just enough water to cover the gold powder and boil for 5 minutes (Removes undissolved and water soluble salts)
6.Let settle and pour or siphon off the water into the stock pot.
7.Repeat three times.

Question: For step 6, do you want to pour off the water while it is still very hot ? If you have to wait another few hours for any suspended gold to settle, won't the salts you dissolved with the hot water crystallize out again ?
Usually, once you've boiled it, the gold starts to agglomerate into larger clumps, so it settles faster
Hi
How much time does it need to settle completely and ready to decant?
Thanks
What is soluble salts
 
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