Why doesn the Speedmaster have sapphire crystal?
Omega uses the plastic/acrylic crystal because it is shatterproof. While sapphire is scratchproof (virtually), it isn’t safe at very intense pressure levels. An astronaute would have a very HUGE problem if his sapphire crystal shattered at 0 G. That’s why it’s used on the Speedmaster Pro and not on the regular Speedmaster’s, it’s intent is to be a professional Pilot/Astronaute’s watch, in that respect it does its job admirably, IMO.
