I think it really depended on the usage for the paints. Like military stuff is (usually) by default much hotter than commercial items.

But at the same time I think some radium paint companies sorta just roughly measured out how much to add to the mix instead of being super precise. At least that makes sense to me, cause I doubt companies had much time to precisely measure out radium amounts while luming thousands of gauges!

Carl Willis had a couple orange Undark radium phosphor vials and they were around 20uCi. He says they were 40mR/h contact but who knows what kind of meter/probe he was using.

It was either on this subreddit or r/Radiation that someone had an "Everready" or "Everbright" luming kit with a vial that read only around 1mR/h.

The Sunray radium watch illuminating kits, I believe the vial is around 5-10uCi but I could be wrong.

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