Yes, CATTIES is a Scrabble word!

Letter values in Scrabble US: C 3, A 1, T 1, T 1, I 1, E 1, S 1.

Is it a valid word?

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

any of various units of weight used in southeastern Asia (especially a Chinese measure equal to 500 grams)
any of various units of weight used in southeastern Asia (especially a Chinese measure equal to 500 grams)