Authenticity Test Kit for Scrap Gold 10K 14K 18K Personal Acid Coin/Jewelry Testing Set Kit includes (1) 10K Acid Test (1) 14K Acid Test, (1) 18K Acid Test, (1) PuriTEST Testing Stone, and instructions Acid changes color to indicate purity Quick, easy-to-use, and provides reliable results Great for scrap gold buyers who use the internet and flea markets Ships to you fast