Kyresearcher said:
Hello, New to this forum...actually came here because of a problem I am having that has now turned into a ungold nightmare..
Separated gold foils from ram fingers using HydoClor acid/peroxide solution... Separated great, filtered out foils and cleaned them with Dist water several times.
Then used hydroClor acid and covered the foils with an inch of headway in beaker... Let stand for 1 hour, then added 5 ml bleach every 10 mins till all foils we're dissolved...
Once dissolved... I let stand and covers for 48 hours to make sure nothing settled.. After confirming no settling... I began adding 1/8 teaspoon of SMB every 30 seconds reaching 1.5 total teaspoons. Reaction takes place slowly... Hours..
Afterwards... The settling is very very fine powder which makes it impossible to pour off solution..
Cannot filter because the fine dust also goes through filter...
11 times I get the same results and can find zero information online..
Any help would be wonderful. Thank you.
One pound of fingers could yield 1.5 grams of gold to over 3 grams of gold depending
on the type of fingers that you were processing. You added a lot of SMB based upon the
amount of gold that you might expect to yield. I normally have added a gram of SMB
for every gram of gold expected plus some more to be sure that all the gold in your
solution was dropped.
The "fine dust" that you are seeing that has precipitated out is probably your little
bit of gold plus the residual SMB that you added. You don't filter this "fine dust" you
wash it using the gold washing methods that are shown here on the forum. I have
used Harold's method for years and it works well for me. Kurtak also has a gold
washing method on the forum which as I have also used with success.
Here is Harold's gold washing method:
Harold's wash procedure
=================.
1. After precipitating the gold with SMB, test for gold in solution with stannous chloride, if present (purple swab) add more SMB until test is negative.
2. Let the gold powder settle to the bottom of the beaker over night.
3. Siphon or gently pour off the used SMB solution into an old milk jug labeled Used SMB. Save in your stock pot or properly dispose of.
4. The gold powder stays in the same beaker you precipitated it in.
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.
11. If you suspect silver is present as a contamination, repeat the process with hot 3% household ammonium hydroxide (unscented- clear). Put these rinses in a separate container and add muriatic acid until no more white silver chloride precipitates. You have added enough HCl when there are no more white fumes coming out of the liquid. Any karat, dental, cpu lid, or gold filled scrap will have silver as a contaminate.
12. Finish up the rinses with three more hot water rinses. Put these rinses in with the ammonium hydroxide rinses.
13. Gently heat the beaker containing the gold powder while swirling the beaker. As the gold dries it will begin to clump and move around the beaker freely. Don't allow the gold to stick to the beaker.
14. When the gold is 100% dry it should be a nice light tan color, if not redissolve it and precipitate again with SMB. Repeating the above cleaning process after precipitation. Good clean gold settles very quickly when precipitated and clumps into nice balls when dried. No gold should be stuck to the beaker when you are done.
15. When completed transfer the gold to a properly prepared melting dish and melt into a button.
Good luck! You are doing good so far! :G