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Ted Mooney, P.E. RET
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Tarnishing Copper Foil
What will turn copper foil tape black? This is the type of copper tape that is used in stained glass. I have been successful in turing the copper green, but I would really like it to turn black.
Christie Markwellhobby - Costa Mesa, California, USA
February 29, 2008
Consult a "patina" book. Several are listed on the home page.
Basically, it will be a sulfide or poly sulfide which STINK! or one using a variant of selenic acid which can be hazardous to your health. I would have assumed that the serious vendors of hobby stained glass products have a reasonably safe product. ( at a high price)
- Navarre, Florida
February 29, 2008
Try potassium,sodium,ammonium or barium polysulfide solution(10 gm/1 lit water).It stinks but it is very effective.Use only fresh solution.There are many other solutions too(all of them are more complicated).
Try Everbrite [a finishing.com supporting advertiser] coating.Hope it helps and good luck!
- Cerovski vrh Croatia
March 4, 2008
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