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bilythepink
04-04-2014, 10:26 AM
I recently found a recipe for granulation paste which includes copper carbonate as one of the ingredients. Does anyone know if this would affect the fineness of the silver for hallmarking purposes ? I was wondering if this would be the case with emersing the granules in copper infused pickle too or if such a small amount on the surface of the silver would make that much of a difference. Maybe I'm not understanding the process enough but would love to give it a go and wasn't sure if I should be using fine silver instead of sterling.

bilythepink
04-04-2014, 11:35 AM
Oh heck, I've just been doing a bit more reading and, as usual, I've got the wrong end of the stick again. Apparently I have to use fine silver as opposed to sterling because of the ability to change the eutectic temperatures of purer metals ... good old Ganoskin atleast I understand why everything doesn't just melt together now. I'm still determined to give it a try with some fine silver as I was trying for a cleaner result rather than just 'blobs' but so much for an inventive way of using up my last bits of scrap sterling. Apologies for my ramblings.

Dennis
04-04-2014, 02:07 PM
The copper coating is easily produced in used pickle, by temporarily dropping in an iron nail, or other such item. The pickle will return to normal behaviour when the iron is removed. The amount of copper added will be minute and dissolve again if dropped into pickle when still hot.
Did you also see the part about keeping the balls in place for fusion using copal resin, Bil? Even so, for larger balls suitable pits made with round burrs are a help.

One way to use up sterling scrap is to lay small pieces in a circle and fuse them together with your torch. You can add more bits in stages until it looks right.
You then smooth the inside with a sanding drum and end up with a random ring, so to speak. The only challenge is to get the size right. Dennis.

bilythepink
04-04-2014, 04:01 PM
Thanks Dennis, it didn't cross my mind that the copper would dissolve when it's dropped in the pickle again. I didn't see the bit about copal resin, I'll have to google that, but the recipe includes tragacanth (something to do with baking funnily enough) which, I believe, acts like an organic glue (I think you can also use klyrfire but that would probably be quite expensive). I have tried using the same method as you suggested for melting scrap, to make 'random' chain links ... turned out totally weird but quite good fun ;)

Recipe : 1 part tragacanth, 4 parts copper carbonate (or any copper salt), 10 parts liquid flux and 10 parts distilled water (courtessy of Carless Codina) incase anyone is interested

Dennis
04-04-2014, 04:57 PM
Oh and I had meant to mention that while granulation gives the cleanest effect, you can simulate it by using flux and tiny scraps of solder. This of course is a short cut and allows you to use alloys of your choice.

Here is my daisy chain brooch. The gold balls were trapped inside jump rings to keep them in place. Dennis.

Summer
05-04-2014, 04:04 PM
Ah beautiful Dennis, the jump ring is a great idea, i was kind of worried my gold balls would fly all over when i did my flower pendant, luckily they stayed put :-)
5927

Dennis
05-04-2014, 05:27 PM
Beautiful Jacqueline, I hope you are wearing it yourself. I wouldn't want to part with that. Dennis.

Summer
07-04-2014, 12:36 PM
Thank you Dennis, I don't actually wear a lot of Jewellery as such, tend to have a few piece's as my fave's though :-)

bilythepink
07-04-2014, 04:36 PM
Two lovely examples, thank you Dennis and Jacqueline :) I did try the guide holes with a bur but they still had that 'sunken' feeling and found that sticking them down with solder paste tends to flood the balls a bit too much ... looks like I'm just going to have the bite the bullet and get me cauldren out.