It's used in tungsten to raise melting temperature and I think it may increase electrical resistance in doing so. I guess it helped Coleman mantels from burning up to fast in a similar way? Bananas are radioactive. K type radiation if I recall. They help other fruits and vegetables ripen. I get a stomach aches from them unless I have ice cream or milk with them. I thought this thread was going to be about some new type of thoriated pick ups. Edit: looks like ESTES used it also. That must be why the cardboard container didn't burn up?