Copper is a wonderful material to use as an inclusion in fused glass projects. The color it turns is a bit unpredictable because copper will react not only to heat, but also to the chemical composition of the glass it is sandwiched between. Most often it will turn into a deep red with bluish or purplish notes. Sometimes it will turn blue. Treated with lemon juice it tends to stay true to its copper notes. Before I gamble with the star I just cut out, I need to make sure I will achieve the desired effect.
My next project needs the the copper to turn red. Step 1 is to take pieces of sample glass and test what happens when the copper is sandwiched between 2 layers.
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| BEFORE |
The top piece has two pieces of clear reactive glass.
The middle has clear reactive glass on the bottom and is capped with clear.
The bottom is 2 pieces of clear.
I fused these to a top temp of 1450° with a bubble squeeze at 1250° on the way up.
THE RESULTS:
The reactive glass causes the copper to turn quite dark....too dark for my purposes...but clear on clear is the magic I was hoping for!
Check back in a few days to see my next steps in this project.


