After weeks browsing through period paper ads, catalogs, consulting private collectors, even digging through the pages of the Library of Congress, here's the long-overdue updated version of this humble work of passion. If Gillette razors are easy to date because of their serial numbers and date codes (and also for being immensely more popular, especially nowadays), the dating of Gem, Ever Ready and Star safety razors is a completely different story. For a few years, a dating chart has circulated around the forums. After I went deep into the Single Edge rabbit hole I soon discovered it was largely incomplete and sometimes incorrect. Also, Wait's "A Safety Razor Compendium" besides being a great source of information and a great starting point, it doesn't cover the many variants and it falls short when it comes to more recent times. This chart remains a work in progress, it may contain errors and it's by no meanings complete. The more I dig, the more information comes to light. But as I considered the dating chart I've posted some time ago has beefed up enough, it was time to make it to version 1.2 Special thanks go to @Ron R for being the first who spread the chart around the forums and for his great job in testing and introducing many Gem razors, to @jmudrick who shared his immense knowledge and made a few well-needed corrections, to master collector Mr. Lorenzi for his enormous effort to display his monstrous collection at Collector's Encyclopedia.com Yes it's getting bigger, please click to "open in a new tab" or save the chart on your computer. By Beta 1.3 I would have to post separate images lol! Feel free to share the chart and publish it wherever you like. No TM or any rights reserved. For anybody who loves Single Edge Razors like I do I invite you to visit the brilliant Gem Razor Models and join us for a Micromatic Monday !