4 Answers

Clear Coatings

Frequently, it is desired to preserve the original salmon or gold tones of copper or brass surfaces. This can be achieved by applying clear protective coatings. The coatings create a weather barrier and prevent the further oxidation of copper, brass and bronze surfaces. However, as with any coating, degradation over time will require the stripping and replacement of the clear coating.

Opaque Coatings

These coatings are used primarily for work applied over copper when substrate integrity and longevity are desired but a specific color other than the naturally occurring copper hues is required.

Paints: Copper is an excellent substrate for a painted finish. Prior to painting, the surface must be free of grease, oil, dirt, fingerprints, drawing compounds and surface passivation treatment chemicals.

A first coat of an industrial wash primer should be applied according to the specific manufacturers recommendation. The finish coat should be two coats of an oil alkyd enamel designed for exterior (or interior) use. Appropriate finish coatings are industrial enamels and silicone alkyd enamels of the specified color.

Gilding: The lamination of very thin gold leaf to copper is a very old tradition. The physical advantages of gold's color and weatherability with copper's sub-surface integrity combine into a very durable, long lived, maintenance free surface. Most gilding is done on historical statuary or domes that are difficult to maintain.

Specifying gilded surfaces includes the following:

Cleaning
Removal of oil, dirt and any surface oxides. Mechanical etch with fine grit sand paper or acid etch to bare metal.

Primer
The application of zinc chromate or VOC compliant primers. Butyl based or moisture cured urethane. Universal metal primer. Two coats.

Adhesive
Compatible with the selected primer. Acrylic size or slow drying alkyd resin, catalyzed marine epoxy.

Gold Leaf

18 gr. per 1000 sheets. 23.5-K gold leaf. Applied to dried adhesive. Burnish.

From Copper Development Asso, Inc.

10 years ago. Rating: 10
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There is a polish and cleaner called Bar Polish, and it is for copper.  Other than sealing it with polyurethane, you must polish it as needed. 

10 years ago. Rating: 9
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I like the green of copper oxide.  A bar top...I can see why you want it polished and preserved. I would go for glass with a copper leaf backing. Assuming the bar is a vintage item, I would go for clean, polish and buff it all...call in a photographer and put on the web for sale with revenues listings for 15 times the gross profits annually after cost as reported to the Tax agency.     

10 years ago. Rating: 6
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My boy cat is a burnished cooper color   :-)  When he lies in the sun, he has a real sheen .

10 years ago. Rating: 4
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