Reply To: c.1915 "Glow-in-the-Dark" Postcard-Hazard?


Indeed, “hard soils” like rhodium where used in photo lenses elements as a coating and that and similar compounds where used in watches and stuff.
In principe, they’re not dangerous since the kind of radiation they have is mostly alpha-waves, that will not event get through the skin.

Anyways I found very interesting and useful if you get to ID the kind of “ink” used in that postal card since documentation from the point of view of conservation seems rare or inexistent. Who know, maybe a lab will even accept to perform tests in it!