Seamaster 2846 lumed hands

ConElPueblo

Radium lume can go black with age, especially in the hands. Have you tried lighting it up with an ultraviolet torch?

Snickers1985

I didn't know that! Wow, I will have to get hold of one of those torches and give it a go. Thanks!

ConElPueblo

Worth a try, I'd say. If the black part is glossy it is unlikely to be lume, however.

Mouse_at_Large

It is likely to be radium 226 in the lume, both on the hands (unless later replaced by an inert filler) and in the semicircular spaces in the bases of the hour markers. Just because it's stopped glowing does not mean it's inert. Radium 226 has a half-life of around 1600 years and is still happily pumping out alpha particles. What's stopped glowing is likely zinc sulphide which has degraded so it no longer reacts to the alpha particle emissions.

The fact that the lume dots on the dial and the lume on the hands is a different colour is not indicative of anything hinky per se. It's quite possible that they were sourced from different manufacturers, the radium based lume applied to them originally may not be exactly the same formulation, and even if it were, it's applied on a different substrate and may be a different thickness. All this may lead to differing colour as it degrades and also different reactions under UV light.