<p>PRODUCTS DESCRIPTION: The 14 K Test acids come in sturdy plastic bottles with internal baffle which prevents leaks to maximize safety and allows the user to precisely drop the amount needed. 12 grams. Use Scratch Stone for determining the carat content of jewelry. Jewelers use these dark test stone to test gold karat as well as silver and platinum. Metal is tested by being scratched onto the surface of the stone. The stone is to be paired with testing solutions and acids to accurately determine the karat content of the scratch that was made. Measures: 2x 1-1/2x 1/4. Professional Use.</p>