This pin looks to me to be very 1980s - it depicts a fashionable lady, with very big shoulder pads, and a large, gold-washed broad brimmed hat. It's a very simple design, unadorned by any design - a silhouette with great style! 3.25" long, 7/8" wide.
The TM registration mark indicates it was made sometime after 1979, when the registration marks changed from the old "eagle" system. T means Taxco; M is the first initial of the last name of the maker; 220 means the 220th maker to register. Alas, few of the registration marks are known, and TM-220 is one of the unknowns.
Excellent condition. A bit of tarnish; I have removed most of it, but have left some on for character. Note that the hat is not discolored, but, as mentioned above, gold-washed. Marked "TM-200 MEXICO 925."