What the hell is Samarium Oxide?

Samarium Oxide, aside from being a neat-sounding extension for my
Internet moniker ("samarium"), is according to METALL:

"Samarium Oxide, also called Samaria, Samarium has a high neutron
absorption capacity, Samarium Oxides have specialized uses
in glass, phosphors, lasers, and thermoelectric devices.
Calcium chloride crystals treated with samarium have been
employed in lasers which produce beams of light intense enough
to burn metal or bounce off the moon."

-Now you know!-