Testing acids come in sturdy plastic bottles with an internal baffle to prevent leaks and maximize safety. Plus, it allows the user to precisely drop the amount needed. Only a small drop is needed, so you will get hundreds of tests out of each bottle! Each bottle contains 12 grams of solution. Avoid ingestion, and contact with skin and eyes.
• Scratch or rub the metal you are testing onto the stone. Scratch hard enough to make a visible streak or mark onto the stone.You may also shave the metal you are testing, and use the shavings to test onto the stone.
• Place half a drop of the closest acid to the karat you estimate the metal to be, onto the gold that rubbed off onto the testing stone.
• If the acid dissolves the metal, the metal is less than the karat that is displayed on the bottle. You should try again with a lower level acid.
• If it dissolves the metal slowly, it is possible that your material is gold, just not as pure as the karat rating on the bottle.
• If the metal stays and does not dissolve, it is at least the karat of the acid in the bottle.