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Old 09-17-2020, 09:26 AM
Josh Bernbaum Josh Bernbaum is offline
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I'd first remove the copper. I don't think that's helping you any.
I have only done light/bright greens with chrome, with iron, and with vanadium. The base batch you're adding to will vary what effects you can expect from the colourants in most cases.
What I would think about trying if doing this myself would be chrome or iron with a bit of nickel maybe? And it'd be a trial-and-error, no way around it, to get to the concentrations that look the best. I like to do small test melts if I have time, which quickly give you a decent sense of the final colour after the batch goes flat in the furnace, although things do darken up a bit in my experience after the full melt/fining process. If you melt 2-5 kilos at a time, then it's easy to multiply for a larger melt later. The chrome and manganese may start getting a bit too brown/ugly-violet for you, because the chrome will 'activate' the manganese and make it have a stronger effect. But perhaps a little bit of manganese with the chrome will steer you towards a darker shade versus the nickel I mentioned. I think whether Gaffer's batch has any potassium in there, or just sodium, might come into play regarding that. Be careful with the chrome, but grind it up in a coffee grinder (Pete's trick) if it's the dichromate form, to get it into a fine powder vs. lumps. And don't skimp on the melt temp to help it go into solution and not form corundum flecks. It may also be the case that all you need is a boatload of chrome to get it to darken up the usually bright green shade it produces in a soda/lime batch. But the more of any of these colourants you add (some more than others of course), the more likely you're throwing off fit with your clear. But if you're not gathering over the colour or mixing it with clear or other colours in any way then have fun and experiment with increased concentrations of these colourants.

Last edited by Josh Bernbaum; 09-17-2020 at 09:38 AM.
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