From Unofficial Handbook of the Virtue Universe
The Bronze Age of Comic Books is an informal name for a period in the history of mainstream American comic books usually said to run from the early 1970s to the mid-1980s. It follows the Silver Age of Comic Books.
The Bronze Age retained many of the conventions of the Silver Age, with brightly colored superhero titles remaining the mainstay of the industry. However darker plot elements and more mature storylines featuring real-world issues, such as drug use, began to appear during the period, prefiguring the later Modern Age of Comic Books.