Building a Silmaril

The news of the development of a crystal that can extract useful energy from radioactivity might be the first step in creating a Silmaril in our universe.

If a crystal is radioactive and can use that radioactivity to pump a laser in the same crystal it would act much like a Silmaril. It would give back any light that it's exposed to amplified. If it were hidden away in Morgoth's horde, the heat from the radioactivity would accumulate and burn anything it touches.