Did Accutrons use Radium or Tritium lume?

Submitted by QuartzCrisis on September 22, 2023 - 9:58am

Is there any historical evidence to know if Accutrons used Radium or Tritium lume?

Obviously American watches didn’t use T Swiss T or T<25 marks on the dial, so is there any way to find out? I’m interested in Accutrons only.

Posted November 26, 2023 - 9:48am

I've found the answer to my own question. Let me share it here so other people can find it in the future.


Accutrons switched from Radium to Tritium in 1963. Collectors report that Accutrons made in 61-62 test Radium on Geiger counter, but the later Accutrons show close to background radiation on Geiger counter (this means Tritium). This also means that all 218 Accutrons use Tritium.