Acid test for platinum & white gold

[donlecat]

Hi,
Hope I''m posting in the correct forum area, but I have some questions on doing acid tests on platinum and white gold to determine the karat weight. I have the necessary acid and stone for doing it, but I''m very unfamiliar with either metal and afraid I''m either not doing the test properly, or not reading the results correctly. And also, do both metals yield the same results such as how they react to the acid? The instructions state that 18K(did not specify platinum or white gold), would begin to change to a bronze color in about 3 minutes. Mine changed within a few seconds to the bronze but I don''t know if that indicates higher or lower karat. It also says that 14K(again not specified), would simply disappear from the stone in about 15 seconds which this did not. Basically I''m totally confused and am hoping perhaps someone with the expertise might give me a little more information to base the test results on. Any help would be greatly appreciated!! Thanks in advance.

Donna

 

[FrekeChild]

14k and 18k are both gold.

 

[Lady_Disdain]

The reliable way to use such tests is to make a streaks with tips of known metal content and compare the reaction with the one you are trying to determine. These tips are usually sold along the stone and acid. Few professionals do acid tests without comparing - the acid may be more or less concentrated, which would change the results.