Catalin and Bakelite are very similar in formula however, there is quite a difference in appearance.  Many people use household cleaners to test for Bakelite and Catalin and since the reaction is the same they feel the terms are interchangeable or that they are the same.  Bakelite is not translucent where Catalin is, the swirled mah jong racks are Catalin and the majority of the tiles are, Bakelite doesn't have swirls.  Neither Bakelite or Catalin come in white, you have to read carefully how some people advertise a "Catalin set" -- of what?  Racks? Well that doesn't include the tiles.  Both Catalin and Bakelite are early forms of plastic.  Hopefully by looking at some of my sets you will see some of the differences.

These sets are catalin.  Please enjoy