Stebgo Metals Blog
When testing for Platinum (PT), a simple test you can do is the heat test utilizing your jeweler’s torch or portable butane torch. All the tools used in this test can be found in your simple testing tool kit outlined in our August 13th blog. The first step in verifying if a piece is Platinum is to look for the stamp. Most Platinum will be stamped with PT, PLAT, PT900 or PT950. The most common percentage is 90% Platinum with a 10% platinum family alloy like Iridium or Ruthenium. The 95% Platinum mix usually has cobalt as the 5% alloy. In the case that your customer wants the precious metal piece back or you want to resell the item, be sure to either take out or protect any stones you may have that could be damaged by the heat. The purpose of the heat test is to see if the piece will remain blackened or discolored (oxidized) after heat is applied and the item has cooled off. Platinum will not oxidize at any temperature; it will simply return to its original look and state. If you are able to, file into the piece in question to get through any Rhodium plating that may be present (See Fig 1).
Old School! Straight Nitric Acid Testing
In my previous blog post, I gave you a list of tools to have in your Simple Testing Tool Kit. One of the major tests you can conduct with your Simple Testing Tool Kit is the nitric acid test. You can purchase straight nitric acid from a chemical supply company. Make sure to refer to the Material Safety Data Sheet (MSDS) when using nitric acid. The chemical supply company must provide you a MSDS with your purchase. Remember to wear rubber gloves to protect your hands and safety glasses to protect your eyes. If you wear eye glasses, I recommend having the wrap-around style of eye goggle that go over your glasses for additional protection. With any acid testing make sure you have an emergency eye wash kit available. Once again, refer to your MSDS for risks and handling of nitric acid.
Last week’s blog showed a simple, portable testing set-up. One of the first lines of defense in identifying non-precious and fakes in your Simple Testing Tool Kit is the magnet.
A common question posed to our staff is whether or not it is possible to have a portable testing kit set up for buying precious metals. We are always happy to inform customers that it is actually very easy and relatively inexpensive to set up portable and reliable testing stations. I have found that many of my clients like to have a portable station in their store, especially if they have space constraints or they have a customer who has requested some privacy. You can easily move this recommended test kit set to another room other than your front counter. I always recommend having both the option of an electronic tester and acid test set up available in your testing kit.