Thank you Topher_!
Tin chloride=stannous chloride method I mean like this video show by Maximov Ro here:
https://www.youtube.com/watch?v=oiYEoP2AhOk.
He took out gold from old DVD. At 6:25 min he neutralized AR with soda (NaHCO3) (not calcined soda). At 8:45 min he used stannous chloride for precipitation. He made stannous chloride, heating Sn in HCl so it is strongly acidic. You can see how he added a bit HCl with syringe at min 10:25 or 10:50. He explained that soda take out tin and it´s not stay in solution. At min 15:40 he´s gotten the same solution what I have with copperas method now. Only difference is: he saw precipitation not me.
I do not know why he would use stannous chloride to reduce gold out of his entire solution. It is merely a test to ensure you know where your values are during the refining process, and the gold that is "precipitated" out, is in the form of a colloid. There are much better ways to actually reduce the gold out of solution...copperas, sodium nitrite, sodium bisulfite, sodium metabisulfite, SO2,
oxalic acid, copper...the list goes on and on. ..the stannous chloride can give a reasonable account of the gold in solution by the strength of the color. The purple of cassius formed can be anywhere from a light purple all the way to jet black.
Platinum, palladium, and rhodium will give their own unique colors when this test is used properly. It is best used with an eyedropper, to test a drop or two of the solution in question. I have no earthly idea why anyone would try to reduce massive amounts of gold with it for the sake of purification, since it can reduce other metals out of the solution as well. ...not to mention the colloidal gold may NEVER settle out..
The other precipitants I listed are much more selective for gold reduction, and they make the gold a nice powder that will sink to the bottom of your vessel, so you can clean it up, dry it, and melt it. If you left your solution alone for 5,000 years, the colloid still may not have settled out, even after that amount of time...
OK
I explain what I did with my 800ml filtered (also diluted) AR what I divided into 3 parts.
A: 1/3 part I used for a method I just described at the beginning
B: For 1/3 part I used hydrazine hydrate 98% what I dropped to my solution (not at home
). I saw a brownish snot occured to the top of my solution what was dissolved after 15 min.
C: 1/3 part i used for, you saw at my video. It was showed step by step. Not any stannous or any chemicals inside. Only green copperas solution (iron sulfate powder+warm water+ a bit HCl in it) what I poured to my diluted AR. I think it could be 50% pure aqua regia and 50% tap water all my solution before I added green copperas solution.
I may have missed it, but how did you remove the excess oxidizer from your AR solution? If there is any unused nitric acid in the AR, it will dissolve the gold as fast as the copperas reduces it to metal. I believe that is your chief issue. It's best to just not overuse it in the first place but, patience is hard to come by when gold is involved. That being the case, the use of sulfamic acid will be of great importance to your refining. It will work double duty. Removing free oxidizer and converting it to sulfuric acid, which converts lead chloride to insoluble lead sulfate.(which can easily be filtered off with the AgCl
I placed copper plate into my black solution now. Thank you for info !!!
Cementing on copper is always an option for a dirty solution, or one with a great excess of nitric, but, keep in mind, not only will you waste nitric by using too much, but you will waste copper in amounts proportional to the excess oxidizer used.
Let see what´ll happen. It´d be the happiest day during 2 weeks if I´d see change in my black solution after several tests. I´m quite frustrated already. No one give serious advice I have asked from some youtubers before.
It sounds like you need to add some extra HCl..
And a little more oxidizer to dissolve the gold from its colloidal state, then put the copper back in to let it cement out. Then gather the black powders and rerefine them using small additions of nitric to the HCl. Letting them work all they will before subsequent additions.
I have that kind of ore on my land I bought filling material some years ago. Now I noticed brownish stones among white brickstones. I was curious to test it because red/brown color looked promising for me.
So what kind of method you would use what would be cheapest for precipitate gold from it? I have not electricity there so I can´t boil anything.