Yes, RUTHENIUM is a Scrabble word!

Letter values in Scrabble US: R 1, U 1, T 1, H 4, E 1, N 1, I 1, U 1, M 3.

Is it a valid word?

RUTHENIUM is a valid word in the official Scrabble dictionary (US), the UK Scrabble Dictionary and Words with Friends (ENABLE).

a rare polyvalent metallic element of the platinum group; it is found associated with platinum

Also: atomic number 44.

Not playable in Scrabble US: RU.