This EASY to use genuine JSP GTE kit will determine the karat value and purity of Silver and 925 Sterling Jewelry, scrap, bars, coins, and much more! Simply scratch the test stone with your jewelry and apply a drop of the acid to the stone and watch the results appear! *Our goal is to make testing your jewelry FUN, FAST, and EASY! *We promise that our acids are guaranteed to be FRESH! *Each bottle will test hundreds of times! *These small bottles are perfect for traveling with or carrying in a purse or briefcase. Quick easy to use; instructions included. *A MUST-HAVE for anyone who invests in silver! This 4 Piece kit includes: - JSP Silver Testing Acid Solution 0.5 oz. - GTE 2''x2'' Test Stone with rubber backing to ensure non-slip desktop testing! Test stone can be used over 100 times! - GTE Neutralizer solution (Used to clean the stone in between each use as to not contaminate further tests) - Easy to read and follow instruction booklet with color chart!