[SHH]

Hi all,
I have an alkaline solution containing gold (AuCl) and over time I notice a pink precipitate forming, any ideas what this would be? 

Also one other question-
I know soft base anion ligands like APDC (a sulfur ligand) complex well with soft acid cation metals like cadmium and mercury, I was just wondering how well APDC would complex with other metals like chromium, cobalt, and arsenic?  APDC = Ammonium pyrrolidinecarbodithioate.
Is there a place I could check the stability constants for these?  I want to keep all metals in solution, no precipitates.  I've heard that APDC can co-precipitate certain metals at certain pHs, has any one heard of this or know any more?

Thanks for the *delete me*

[AWK]

Google: Ammonium pyrrolidinedithiocarbamate complexes

[SHH]

Hi, thanks but I've done that and couldn't see the exact information I'm after.  If you have a link or reference I'd be happy to read.  Or if you know the answer I'm here also.
Cheers