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Please could you help me. I am fusing copper foil inbetween 2 pieces of 3mm tekta. It has turned blue instead of red. Is this because I am fusing at too high a temp or too cool. I am heating up at 222 - 677 leave 10 min. then 333 - 795 and leave for 5 min then afap - 482 and leave 1 hour then 100 per hour to 300 and then off, I have never had any problems with foil before but cannot quite remember what firing i used to use. Also I am using 5cm squares of glass

Thanks for your help

Copper will turn bluish if it's thin, turn reddish if it's thick.

To get a reddish color, you'll need to use copper that's slightly thicker than the copper you're currently using.

You are lucky. I've never managed to get the copper to turn blue. Maybe I should try foil. What thickness of copper are you using?

I have been told the difference between whether copper will turn red or blue depends upon how much air gets to it. Fuse copper between pieces of glass and it will turn blue. If you put the copper down on the shelf first and top with glass, the copper will turn red. My wild assumption is if you provided a pathway for air to get to the copper (for instance, chads), that you might get a more reddish color.

haven't tried this myself, but it's on my list (along with a million other things!)

Dana W.

If you don't sandwich the copper between layers of glass it will turn black and burn away. It may be because I always used float glass and the air got to it longer before the glass sealed on the edges.

jolly wrote:You are lucky. I've never managed to get the copper to turn blue. Maybe I should try foil. What thickness of copper are you using?

The thin copper Bullseye sells turns blue when sandwiched between glass and full fused. The thicker 36 gauge tooling foil you can buy at most craft stores turns purplish.

jolly wrote:If you don't sandwich the copper between layers of glass it will turn black and burn away. It may be because I always used float glass and the air got to it longer before the glass sealed on the edges.

Perhaps that is your experience, but I have seen a piece where the copper was on the kiln shelf, and while the backside/shelfside was dark, it did not burn away.

Dana W.