Featured image: 7,000-year-old skeleton of woman may have been a victim of leukemia, making it the oldest case found.
Story highlights. Colorado began allowing the sale of recreational marijuana on January 1 to anyone age 21 or older. Residents can now buy marijuana like alcohol -- except the cannabis purchase is limited to an ounce, which is substantial enough to cost about $200 or more.
Marijuana's use by qualifying patients had been quasi-legal in Colorado for almost a decade, since voters amended the state constitution in 2000 to allow it. But there were no statewide regulations governing its sale and distribution. The federal ban still trumps Colorado's state law, but enforcement was light.