Hi all, This is my first posting and greatly appreciate any and all help given. I have had no issues with Karat and Vermeil refines. In-fact I love Gold Vermeil and have been doing that for a long time. But I wanted to give Gold filled a try since I have had a stockpile building of it for a very long time. By all accounts everything I had seen and read told me it should progress the same as I do my Vermeil. I have been using Harold's step by step process for that and never had an issue. Vermeil uses way less Nitric and dissolves so easily sometimes I don't even need heat. But then the Gold filled has me stopped in my tracks because I don't want to proceed without some guidance. So I checked all my pieces and found definitive markings of either 10K, 12K, or 14K 1/20 gold filled on all pieces. I gave them a quick torching to glow off oils and grease. I did my calculation at needing 3482ml of nitric to complete the base metals. I had no time constraints so I was going to do small dilute nitric baths and just go till all base metals were gone. Things started great. I was going 700ml distilled, adding 300ml of nitric to start. Got a great reaction of swirling and bubbling. Let that run till it visibly calmed down, added another 100ml of nitric. Let it calm again, and add one more 100ml nitric, then after it calmed let it cool and pour it off and repeat that formula till all base was exhausted. The problem is the first 3 cycles of that ran as predicted, but the 4th started to react with just a bit of brownish yellow fume building up under my watchglass and then nothing. I turned up the heat and still nothing. Since this was from a previously opened bottle of nitric it had me almost thinking my acid could have degraded. So I poured off that solution and opened a new bottle and added a fresh cycle and still nothing. I went and pulled a decent sized Gold Filled chain from my stock and tossed it in the previously poured off cycle of solution(the one I thought could have been degraded acid) but it immediately reacted and dissolved it in a rapid period of time. I took my stirring rod and tossed around what id left in my initial base material beaker and it surely seems to be a lot of material left. A few even seem to be hardly started to dissolve. Plus my Nitric usage had only hit 2000ml which is way off my calculations of what I had figured needing to complete the process. So at the start I was sure I had no stainless in this batch, but now I'm second guessing myself. So what would be my best next step to eliminate loosing any gold I have gotten to this point. And or how to proceed from here. Thanks
Gold filled refine not going as I had hoped
- Thread starter SinisterGenuis
- Start date
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Nitric will do NOTHING to real higher karat scrap. 10k can sometimes react slowly if it's high percentage copper, from my experience. Did you cut the gold-filled material at least in half? 14K GF may not react at all if it's the higher-quality GF, since the acid cannot penetrate the gold to attack the base metal beneath.
I process Gold Vermeil the same way I am processing this GF. I have never had an issue with the acid penetrating the Gold coating on the Vermeil and its my understanding that the coating on Vermeil is better quality than on GF. I am Following Harold's method and it does not mention inquarting before Nitric. A long time ago in a post I also asked that of Sreetips and he told me it would become colloidal and make it harder to separate.
If you have separated it from its base metals and the rest is over 6 karat it needs to be inquarted in the meaning brought to 6 karat.
You can avoid this if you canntumble it or otherwise remove the coating of Silver Chloride mechanically during dissolution.
Or it is so thin the AR gets to the Gold through the layer of Silver Chloride.
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So in reply to your first sentence thats the hurdle I'm having. I find it hard to beleive that i have in fact removed all the base metals. I also highly doubt any of these pieces were karat gold only GF. If I may ask why would I have silver chloride at the dilute nitric bath stage.
Of course there are karat in Gold filled.
They would never use pure Gold as it is too soft.
And the Silver comes from the karat alloy if you put it directly into AR, which can be done if you tumble or other wise mechanically disturbs it.
