Antiquing Bronze

A patina is the discoloration on a bronze or brass piece.

For centuries, bronze statues and jewelry have been oxidizing, which causes bronze molecules to change color. This antique look is now prized in the world of art and fashion, and now designers want to take new pieces and "make them look old." While arts and crafts stores sell products that speed up the "antiquing" process, the ammonia vapor method does not require industrial chemicals and is safe to do in the home. In addition, since copper is the element in bronze that chemically reacts in this technique, it can also be used to add patinas to brass, another alloy with copper.

Things You'll Need

• Bronze or brass object
• Soap
• Water
• Soft rags
• Ammonia
• Large jar or storage container
• Nail
• Fishing line
• Beeswax

Instructions

1. Thoroughly clean the entire surface of the piece being antiqued using soap and warm water. Remove all waxes, lacquers, oils and varnishes.

2. Dry the entire piece using a soft cloth.

3. Tie the fishing line to the piece.

4. Punch a hole in the lid of the jar or container with a nail, and thread the line holding the piece through the hole.

5. Fill the jar or large container with ammonia, leaving enough room in the container for the piece to be suspended above the surface of the ammonia.

6. Hang the object above the ammonia's surface, and secure the lid on the jar. Tie off the fishing line suspending the piece so that the piece does not touch the surface of the ammonia.

7. Check the piece daily. Replace the ammonia in the jar each day to refresh the vapors.

8. Remove the piece from the jar and the fishing line once the desired coloration is attained, and rub it down with beeswax to seal in the patina.

Tips & Warnings

• Avoid breathing in ammonia fumes. Keep the jar or container in a well-ventilated room.

• If the brass or bronze touches the ammonia, clean the ammonia off the surface and resume the process. Ammonia can stain bronze.

• Mix water and baking soda with the used ammonia before disposal. Ammonia can sometimes cause damage if poured down old pipes.

References

• Jem Library: How to Antique Brass
• SteamPunkLab: How to Age Brass
• Wagner Cos.: Antiquing Brass or Bronze