VTG Enamel Lapel Pin American Institute of Electrical Engineers Lynn MA AIEE

This was the second logo for The American Institute Electrical Engineers, used from 1898 to 1962. While the green and white are obviously enameled, I don't know what the metal of the structure or in the design is. Some were made with actual gold, I do not believe this model was, but, as I can't find any to compare it to, possibly. Lynn MA local section. Measures about a half inch diameter.