Hello Alondro, how did you dissolve your gold? My understanding is that it will not dissolve in straight HCL. I did not know about boiling the leftover solids, I will have to look into that. I just started recovering and am learning a lot. I printed out a copy of Hokes book and am studying it now as I go. I know, and have been reminded many times to read it first but with what is going on I have a limited time to get done what I want to do before travelling south again and will not be able to take my hobby with me.
The HCl, plus a little copper chloride to jump-start the reaction, will eat away all the base metal. It takes a week or two at room temperature, depending on how thick the base metal is. Warming it speeds the reaction, but I'm never in a hurry so I just let it do its thing in our boiler room, where it's very hot anyway, and gets ventilated heavily. If you don't have a ventilated boiler room, but have hot summer sun, you can save energy by sticking the beaker in a make-shift greenhouse. In summer sun, it'll hit about 150F or higher in any enclosed space with transparent glass/plastic covering and a dark-colored floor.
You'll be left with gold foils/fragments and a concentrated solution of copper/tin/nickel chloride (mostly copper). You pour that out (filter to catch the fine gold particles that get stirred up), wash once with a little clean HCl (adding water for the first wash will cause formation of insoluble tin oxychloride and precipitate copper (I) chloride which is rather insoluble in water), and then once or twice with hot distilled water to get rid of base metals still in solution on the foils.
Then you add HCl again to the foils (and the washed filter with the gold particles), just enough to make a layer of liquid over the foils, and then add bleach a tablespoon-full at a time (or more if you have a LOT of foils, let's say if it feels like you might have an ounce or more), heat gently with swirling. If all the gold doesn't dissolve, add a little more bleach and stir some more (thin gold foils should dissolve within 15 mins if there is sufficient chlorine being generated in the HCl-bleach reaction). If they still haven't dissolved completely, add a bit more HCl and a little more bleach.
Once dissolved, you should have a nice pale yellow-orange-ish to DEEP orange-colored gold chloride solution (depends on how concentrated it is). Simmer this slowly outside for a few hours, but don't let it boil, (in direct sunlight it works even faster) to drive off the excess chlorine. Then you can cool it down and drop the gold with SMB. The drop should work very well, since there's no chance of sneaky nitrate anywhere in the solution.
Thick gold, such as jewelry, doesn't dissolve well with this method. It's VERY slow and you have to keep playing with the solution all day to get it to completely dissolve. Thick gold requires either AR, or Sreetips method of alloying the gold with the right mass ratio of silver, then dissolving the silver and base metal contaminants with pure nitric or sulfuric acid.