From this my personal break down is
golden age - pulp heroes, emergeance and proliferation of powered masked men, 40s through the 50s
Silver age - Marvel age, Barry and Hal, 60s
Bronze age - Kung Fu, blaxploitation, horror books like Tomb of Dracula, Werewolf by Night (reflecting changes in the comics code), 70s
Cooper Age - mid 80s-to very early 90's, tight line wide continuity, Shooter era, post Crisis
Chromium? Foil? Extreme? age - Extreme Justice, Harras Avengers, X-Men explosion, Image founding books
Cinematic? Celluloid? - widescreen, "thoughtful" storytelling, Warren Ellis, Ultimate Marvel, late late 90s-2000's
Digital? - new 52, Marvel Now, '11/'12 - current?