I didn't know about this one, but I see it is in TCR as V5528, apparently added in the last revision. According to TCR, the only other Sands $50 is the plastic baccarat chip.

Value is listed as L, but I would bump that up 5-6 letters based on the scarcity and popularity of Sands Las Vegas. Chip is unused, and possibly one of the scarce chips sold out of the vault after closing. May have never been issued?? I would guess it's a promo chip for invited guests.

Colors are blue with extra-large (1") hot-pink inserts.