3 Pack Gold Testing Solutions $20 Value! 1/2oz bottle purity testing solutions provides fast test results! Testing is sensitive to within about +/- ½ karat! or about 2%. Only a small drop is needed to test, so you will get hundreds of tests out of each bottle! Easy to follow instructions included! 2x2" PuriTEST Pro Testing Stone $10 Value! The PuriTEST PRO STONE testing stone to be used with testing solutions to test the purity of precious Bullion Nuggets, Ingots, Bars & Coins such as gold, silver, & platinum. Dimensions: (2 x 2 x 1/4)in