Summary for stopping copper oxidation Discussion
Stopping copper oxidation is the core problem in this metalsmithing thread: Michael McGoey says his silver-and-copper jewelry looks right after liver of sulfur patina and steel-wool highlighting, but the copper turns reddish brown and spotty within days. He says wax and epoxy have been suggested, but he doubts they will last long enough for sellable, “timeless” pieces. The only answer shown is a brief recommendation that some commercial products, including eBay items, contain benzotriazole or another tarnish preventive, and that these may last for a few years. No one in the excerpt offers a permanent fix, and the discussion implies that any coating or inhibitor may only delay oxidation rather than stop it forever.
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
⇦ on
eBay or
Amazon [affil link]
to create a dark patina. Next, I use 00 steel wool
⇦ on
eBay or
Amazon [affil link] & 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 A. Some aerosol lacquers which are specifically designed for brass/copper alloys like Incralac ⇦ on eBay or Amazon [affil link] ⇦ on or Amazon [affil link]
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