The El Cortez is definitely a USPC chip NOT Burt. Based on the chips in my collection, the date range would be 1911 to 1946. I would date it to the 1920s or 1930s. I have very few 1940s. Actually the only 1940s chip (1946) I recall is the Clifford Albert personal chip which was made by USPC for its former president. The last commercially made c&s by uspc may have been in the 1930s.

USPC-made Nevada chips include: Bank-Palace (1931), Cal-Neva (1937), Country Club (1935), Fortune Club (1937), Golden Club (????), Jimmie Casino Club (1925), Reno Commemorative (1932), Palace Club (?????), Stray Antler (1927)