Crowncap Manufacturer card
  
Entered: 24 Feb 2020 22:16 - Michael Dolgushkin - Modified: 05 Apr 2021 22:03 - Jon Bailey
Jeffco Manufacturing Company (JMC)

Denver, CO. Manufactured Coors crowns from 1964-1976. Responsible for some Pepsi-Cola crowns as well. At least some Jeffco crowns appear to have been made by HC, which begs the question of whether they actually manufactured crowns at all or were a shell corporation that farmed out the work. It seems significant that JMC also stands for "Joseph M. Coors."

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Maker's Mark