Not sure Brownish after stannous

[j2000]

Hi, I got color brownish after giving stannous to my AR.

I clean using weak HCL (clean the Fe), and filter it, the rest on the filter put on AR, and check after few hour the color of stannous test from yellow color (not orange) to be brownish...

I just not sure as i expected is AU..

Regards

Joel

 

[Geo]

Looks like a false positive to me. SMB can precipitate palladium if there is an excess of SMB in solution when the gold drops. It will also precipitate copper at the end of a gold drop. If you test a sample with stannous chloride and it still has SO2 gas in solution, it will make a brown stain to appear.

 

[solar_plasma]

How old is your SnCl2-solution? I did see this strange reaction a few times when my stannous was too old.

 

[j2000]

Its fresh stannous, also i got pure gold already in AR as my comparator, result from this stannous to my comparator gold + ar = Purple, same as manual

 

[g_axelsson]

Stannous with sulphur compounds can give a brown stain. What is your starting material? Give a bit of a background.

Göran

 

[j2000]

Stannous with sulphur compounds can give a brown stain. What is your starting material? Give a bit of a background.

Göran

Thanks goran, it's possible sulphur...its from ore powder...
Because i dont clean the sulphur first...

This link is related to this post, also my link about cleaning Fe + Sulphur...using HCL with or without incenerating first,..
http://goldrefiningforum.com/~goldrefi/phpBB3/viewtopic.php?f=37&t=23169&p=243199#p243199

Btw, i will start incenerating/roasting the powder from ore first, and re test...