TESTING FOR GOLD
Scratch the piece to be tested over the surface of the black stone (Item #: GT-33); press well so as to leave a visible deposit that is preferably one to one and a half inches long.
Transfer a drop of the 10k solution (Item #: GTS-001) to the scratch made. If the solution dissolves the scratch on the stone, it means the object is less than 10k gold or not gold at all. If the solution leaves the scratch intact, it means the object being tested is 10k or greater than 10k.
The scratching and testing is repeated with the 14k solution (Item #: GTS-002). If the solution dissolves the scratch on the stone, it means the object is less than 14k gold (If the scratch dissolves slowly and leaves rusty color particles, it is probably 12k gold). If the solution leaves the scratch intact, it means the object being tested is 14k or greater than 14k. (CAUTION: Many objects are marked 14k, but were fabricated prior to 1982 when it was legal to mark items 14k, but in reality the gold was 13.5k. When testing 13.5k gold, the 14k solution will not dissolve the scratch, but it will make it lose its brightness and it will turn into a yellow-rusty color).
The scratching and testing is repeated with the 18k solution (Item#: GTS-003) and 22k (Item #: GTS-004) solution (if available) until the karat of the object is determined. (Remember that when the solution being used dissolves the scratch slowly and leaves rusty color particles it is probably two karats lower than the solution being used. For very accurate testing it is recommended that the user becomes familiar with comparative testing using standard gold testing needles [Item #: TESTING]).
NOTE: On items of heavy weight and volume such as chains, coins, etc. where plating could hide the true metal, it is recommended that a deep notch in the test piece be made and the testing be made with the metal inside the piece.
TESTING FOR SILVER
Scratch the piece to be tested over the surface of the black stone (Item #: GT-33); press well so as to leave a LARGE AND THICK visible deposit that is preferably a line of one to one and a half inches long.
Transfer a drop of the RED silver solution (Item #: GTS-101) to the scratch made. The color reaction of the solution with the metal will be as follows: (Take into consideration that the background of the test stone is black).
NOTE: With the silver solution, it is possible to test directly on the piece being tested; however, the solution will dull the polishing of the piece, and leave a mark where the acid was placed.
TESTING FOR PLATINUM
Rub the item on the test stone and apply a drop of platinum solution (Item #: GTS-005). The platinum mark will remain the same white color with no reaction.
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