When testing for blacktopping on IC’s the use of acetone has been the accepted method used when inspecting parts purchased from the open market. The counterfeiters figured out years ago that acetone was being used and they have adapted by getting smarter. Many of the top coatings now are baked on using acetone resistant materials. Using a simple razor blade is an easy way to test any top coating. Sometimes the results are hard to read, but it is usually clear that there is a layer on top of the plastic if you are using a microscope. Here is a great example of some parts that we caught today.