What did the pin test smell like? Chemicals or burning hair?

I'm almost certain that these are a synthetic (celluloid or not). The scales are very thick to be ivory, the color is off, this faux style puts very strong Schreger lines in (they stand out more than in real ivory, and probably don't have the right 3d/surface look), the pins have collars, and this exact type of faux was used on a lot of razors around this age. Without inspecting it in person I wouldn't know for sure, but from all the clues I'd say faux ivory.