Gosiba Acid

(San Antonio, Texas)

I would like information on using Gosiba on an argentium & 22k gold piece. I want the argentium black and keep the gold bright and looking like 22k! Do I dilute the gosiba and if so, what are the portions?

Stacy's Answer:

Hi Mary!

I use the Gosiba straight - no diluting. Simply wear a latex or similar disposable glove(s) and dip your jewelry item in the solution for about 6-7 seconds. You can also brush the product on. Make sure your item is completely finished (polished, etc.) and clean before dipping. The Gosiba black patina is pretty durable (it can lighten up some in areas that make contact with the skin) and rather difficult to remove. So be sure you want the silver black before applying.

Rinse with clean water, let dry and tumble-polish if you desire. I've found that a short (one hour or so) tumble helps to darken the patina instead of it looking dull and slightly hazy. You can also use Renaissance Wax to help darken the patina and preserve it.

Store the product in an airtight plastic container (like the plastic bottle it comes in) away from sunlight and be careful not to contaminate it with water, baking soda, etc. Stored properly, it lasts a long time. Leave it out on the counter where the sun can get at it and it'll go inert withing a few weeks.

Black and gold is a very cool look. Have fun using it with your designs!