Pickle is a liquid compound used to remove oxidation and flux from newly soldered jewelry. It is what you put your pieces in to clean them after soldering. Metal that has been soldered produces oxidation on the outside of it. Allowing the metal to cool and then dropping it into the pickle removes the oxidation. The metal should also be pickled before the soldering process to clean it.
Pickle works best when it’s heated. A small crock pot with a lid is recommended for containing the pickle. Keep it on the Low setting. If the lid is kept off, the pickle will evaporate. Distilled water can be added to replenish it.
Pickle lasts for a very long time, but when it starts to turn blue from the collected oxidation then it is time to change it. The solution must be neutralized before it’s disposed. Pour it into a separate container and add baking soda until it stops frothing. No frothing means it’s neutralized and can be disposed at a hazardous waste dump.
Pickle works better and faster when hot. An old crock pot with a glass lid works very well for a pickle pot. Sparex no. 2 is a good pickle and is a lot safer than some of the acid concoctions used for pickle.
You will also need a pair of copper pickling tongs for removing pieces from the pickle. Pickle tongs are made out of copper because copper doesn’t react with the pickle. If the tongs are made out of a ferrous metal they will react with the pickle and your pieces will end up with a thin copper plate on them.
Types of Pickle Available
Many jewelers are using biodegradable pickle in lieu of toxic compounds found in regular pickle. However, while the natural pickle is environmentally friendly, it is not a strong as chemical pickle and must be changed often.
- Citric acid – add a few tablespoons of citric acid purchased at any grocery store to a few cups of distilled water (always add acid to water). This does not need to be neutralized before it’s disposed.
- Vinegar – add 2 teaspoons of salt to one cup of vinegar. These both can be purchased at any grocery store. This does not need to be neutralized before it’s disposed.
- Commercial-grade citric acid – follow directions on the container to add the proper amount to distilled water. Neutralizing is recommended before disposing.
- Sparex #2 – a sodium bisulfate liquid that is the most popular pickle choice among jewelers. It comes in a granulated form to be added to distilled water. It is toxic and will ruin clothing that comes in contact with it. It must be neutralized before disposing. Copper tongs must be used for extracting the jewelry as tongs of another metal will contaminate the pickle. Amazon has Sparex #2 available in 10 oz and 2 1/2 lb. bags.