The tritium on my Rolex from the 1980s no longer glows in the dark.
“The tritium on my Rolex from the 1980s no longer glows in the dark.”
Tritium doesn’t glow. It is probably the phosphor material that has broken down. Although the tritium has gone through about 2.5 half-lives so its activity has been reduced to about 1/5 of the original. So maybe it glows but not so brightly?
At least with radium watches, the only thing that is needed is to renew the phosphor coating (ZnS): the radium itself will outlive you by far.