Gold pins...

[Slochteren]

Hello,

i'm Paul from the Netherlands, also excuses for my englisch if it is not all correct. I ended up on this forum after searching for some info on how to process gold plated pins.
I have read a lot on this forum by now and have read some portions off Hokes book. But being impatient i started following the steps as described on
http://goldrefiningforum.com/~goldrefi/phpBB3/viewtopic.php?f=52&t=7093&start=80
Till now everything went as expected and described. At step 11 i burned the black powder en filter, i didn't melt it just till red hot, only the black powder is not black anymore but light brown.
I have transfered it as described to a beaker and let it setle but also the filter remainings (ash) is setled. I have read the following steps but don't read anything were i get rid off the ash, or it must be with the filtering after AR.
Before proceeding i would like to have some info about the ash.
Don't know if its because i used a stainles steel cup for the burning, i started with casserole dish but after testing how heat resistance they are 2 broke and after those 2 my wife would'nt give me another one... also i used a stainless steel cup.

How it looked after burning in the stainless steel beaker

How it looks now from above

How it looks now from side

Thanks in advance.

 

[MrMylar]

Did you put the pins in a sulfuric cell? If you did, then that paper should be if not, completely gone. It won't hurt that the paper is there, but all that ash will cause some contamination and will require some extra filtering.

Since you've added solution to it, test it with stannous and see if it's positive or not for gold.

Also, the black powder does change to a brownish color after incinerating it. That's normal.

If you used AR to dissolve the powder, then there shouldn't be anything at the bottom of the jar except the ash. When you filter the solution, use at least 6 coffee filters so it will capture most, if not all of the ash. If the solution isn't clear, regardless of the color, you should filter the solution some more through the same filter set you used to trap the ash.

 

[Slochteren]

There is now only the hydrochloric acid in wich i used for transfering from the Stainless steel cup to the glas conatiner also there should not be any gold dissolved in the solution. Also i can continue to decant the acid to my waste container and adding fresh hydrochloric acid and heat up a litle and start adding nitric acid. The ash will be removed after the solution is filtered after AR?

 

[MrMylar]

Since this is just coming off the incinerator and all you added was HCL, then all you need to do now is add a small amount of Nitric Acid and let it do it's heating up, and then place it on low heat. From the photos I would estimate around 10ml Nitric to start out with. You can always add more of it, but you don't ever want to add too much of it.

The solution will brown up and red fumes will come out. You don't want to be anywhere near it when it does. Keep a watch glass on it, but let it breathe. After the reaction stops, turn up the heat more and see if it stars to react. Don't forget to stir with a stir rod. Stirring sometimes without adding more heat can restart a reaction. I've stirred my solution while on the hot plate and then it started reacting again. Some of the gasses and other elements in the solutions can be trapped by powders, papers and other junk.

Once everything is dissolved, all you need to do is test for gold, filter the solution and then drop it with SMB.