Yes, SPIEGELS is a Scrabble word!

Letter values in Scrabble US: S 1, P 3, I 1, E 1, G 2, E 1, L 1, S 1.

Is it a valid word?

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

pig iron containing manganese; used as a deoxidizing agent and to raise the manganese content in making steel

Also: spiegel iron.