[Arran]

Many of these Addisons are actually made out of Plascon not Catalin, it's also coloured but it isn't semi translucent like Catalin is, you can tell by shining a light through the back of it. Some of the later models have brown Bakelite cabinets, but there were also ones with wooden cabinets as well. Bakelite is similar chemically except that the resin is ground into a powder and stamped into form in steel molds under high pressure and heat. With Catalin the mixture is cast in liquid form by pouring into a mold like a candle. I have one of these with a broken cabinet, but it's a Plascon one.
Regards
Arran