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Stopping Copper Oxidation

Q. I am a metalsmith creating jewelry out of silver and copper. Once my jewelry has been completely sanded / finished, I dip the piece into liver of sulfur ⇦ this on eBay or Amazon [affil links] to create a dark patina. Next, I use 00 steel wool ⇦ this on eBay or Amazon [affil links] & cold water to remove some of the LOS and create highlights. The steel wool and cold water work well to bring the copper 'shine' to exactly where I want it. The issue is this, after a few days, the copper turns reddish brown and begins to show various signs of oxidation i.e. color change, spotty etc... As a jeweler, I cannot sell pieces that look great on day one and then look terrible on day 12. I've heard about people using wax and epoxy to retard the oxidation after the proper 'shine' has been achieved. I've been told that this works OK but eventually wears off and the copper oxidizes - again, not a viable solution for 'timeless' jewelry pieces.

I'm hoping someone can help. I don't have the budget to substitute gold and really want to keep developing pieces with silver / copper. I cannot however sell jewelry that slowly changes over time. I need to find a solution that helps solidify the look of the piece at the point it is finished.

Michael McGoey
Metalsmith - Boulder, Colorado, United States of America
2007

A. Try Everbrite [a finishing.com supporting advertiser] coating.You can use baked shellac (20% in pure alcohol or methylated spirit,30 minutes at 150 °C; it can be dyed with wood finishing dyes) too. Hope it helps and good luck! Goran Budija - Cerovski vrh Croatia A. Some aerosol lacquers which are specifically designed for brass/copper alloys like Incralac ⇦ this on eBay or Amazon [affil links] or Permalac [adv: Permalac on eBay] contain benzotriazole ⇦ this on eBay or Amazon [affil links] or another tarnish preventive. They might last for a few years. Jeffrey Holmes, CEF Spartanburg, South Carolina