B.P.O.E. 45 year service /member / organization pin

Vintage Elks Lodge Tie Tac B.P.O.E.. Benevolent and Protective Order of Elks Vintage Elks Lodge Tie Tac / Pin, marking 45 years of service / membership. Not sure if this is a rhinestone, or diamond. The background is a deep royal blue but shows lighter in the photo. 3 dimensional. This is so nice and in great condition. Measures 5/8" dia.