CraftWEB Hot Glass Talk

CraftWEB Hot Glass Talk (
-   General Hot Glass Discussion (
-   -   Surface metallic copper (

Sean Jones 08-15-2020 04:27 AM

Surface metallic copper
I made a nice turquoise with copper in my wire melter but got a reddish film on the outside of the vessels. Itís only obvious where Iíve gathered over an opal but it looks terrible.
I can only assume itís metallic copper reduced by blocking. Is this a common problem or just poor blocking technique?
I had 42g of red copper oxide in 25kg of critalica (5.4g per 7lb). Made the blocks out of local cherry wood.

Pete VanderLaan 08-15-2020 10:54 AM

I would suggest you use black copper instead of red copper. You could also consider adding a small amount of either potassium or sodium nitrate , probably the same number of grams that you are using of the red copper. Oxygen will tend to discourage the plating you are experiencing.

It's Cristalica.

All times are GMT -5. The time now is 10:15 PM.

Powered by vBulletin® Version 3.7.2
Copyright ©2000 - 2020, Jelsoft Enterprises Ltd.
© Opportunity Network. 2008. All Rights Reserved.