the coaster is a guess but i would say 60's. my reasoning is because of THE SANDS . if you look at the chips on the chipguide some from the 50's and the brown $1 from 1964 go by THE SANDS. by the 70's the chips were simply SANDS. hopefully someone older and more knowledgeable on sands las vegas chips will chime in. dating things from sands AC is easier to date based off the 5 different logos used over the 25 years.