Art Clay Silver - Black and blotchy after a few hours wear - Help!

Hi there

I have done a few searches on this and have seen that other people have had the same problem with silver clay. I made a necklace for my sister-in-law which was perfect when it was sent and when she took it out of the box, but when she wore it for under one hour it turned a true black colour, blotchy in parts. She had put some perfume on so I was thinking this could be the problem. However, when I visited her I re-polished it all to it's silver shining glory and I wore it myself for a while. Nothing happened. Thinking that I resolved the problem my sister-in-law then wore it for a few hours without any perfume etc and the front piece (there are 2 discs that make up the necklace) the front piece which was not even in contact with her skin started to go black and blotchy. This makes me think that there is something in the clay that is seeping out and it is not a surface problem. Has anyone come across this before? Any help or advice would be appreciated as I do not want this to happen to my paying customers! Could it possible be contaminated clay?

Thanks.

Given that precious metal clays are somewhat porous, did you pickle the item and if so could it be the pickle that is leaching out and discolouring your piece? I know I have to be careful as I use sulphuric acid and I know for sure it needs a lot of rinsing and neutralising, otherwise I sometimes get a similar effect.

Yes, I did pickle the sterling jump ring that I had soldered on to it but did not immerse the pendant in it but I guess that the pickle would have touched it. I did neutralise it afterwards too. I normally do this with all my pieces so this is why I am so baffled. Do you now if there is anyway to rectify this or get rid of the pickle if it that is the problem?

I only know about acid pickle, and once I had realised that that was the likely cause I neutralise with bicarb, give them a thorough soaking in water, then tumble, after which ummmm well I stick my tongue on them to see if they are still acidic if not I deem them to be fine.

I am guessing that a good long soak in hot water or maybe even boiled, done a couple of times, you will soon know if it is going to happen again.

I have some vague memory of a thread about this in the past, you might try searching to see if you can find it, and if memory serves me correctly, it was suggested that there could indeed be contaminated batches of metal clay. It was some time ago and I am not very good at searching this site.

By process of elimination it may well be the pickle. I will give it a try when she returns the piece and in the meantime make another piece with the same clay to see if it is that. Thanks for your help.

Well I have been looking back through the threads and found two but not the one I was thinking of

http://www.cooksongold.com/forum/sho...+turning+black

http://www.cooksongold.com/forum/sho...+turning+black

Oh yes, these are the ones I saw too, something is causing it but what!?? I am off to pickle a scrap of silver clay to see if happens to that!

Is Art Clay the same as PMC3, I have made several things with PMC3 and not had a problem, I cant remember putting it in pickle, just put it in my barrel tumbler.

Try neutralising the pickle in a solution of bicarb. This can even be boiled if you really think this is the problem.

Hi there

Yes, it is the same as PMC3. It's just that I soldered a jump ring to a pendant and had to pickle the jumpring to clean it up but in the process pickled the art clay too and probably did not neutralise it properly.

Just to let you know if anyone else does come across this problem I seem to have rectified it. I think it may have been the pickle causing the problem. I put the pieces in hot water and bicarb of soda and re-fired the couple of pieces a couple of times and re-polished. Seem to be ok so far...

Thanks for the advice.:D