Keystone beer is a product of the Coors Brewing Company in Golden, Colorado. It was first introduced in Chico, California in September of 1989. Due to its relatively low price and popularity amongst college-aged individuals, it is often considered a cheap beer or, when purchased in case-form, a 'dirty thirty'. Its low price also makes it a great beer for Beer Pong and also Beer-Ball. They are also known as "stones".
It is a second running beer of the Coors Brewing Company. Because Keystone comes from the second-run portion of a batch of Coors, it has a lower price. According to the Coors Brewery tour guides however, Keystone is not a second run, or run-off, beer, but actually has its own recipe and brewing standards. Keystone can be found in can, keg, and occasionally bottled form. The official slogan of Keystone Light was formerly "All Stones Must Be Thrown," and it was marketed as "bottled beer taste in a can" (according to Coors, this was due to specially lined cans). Another Slogan used for Keystone Light called it the "Never Bitter Beer," and the commercials touted it as a remedy for "Bitter Beer Face." The current slogan is "Always Smooth."
Four varieties of Keystone have existed:
* Keystone, found with a bright red label
* Keystone Premium, found with a maroon label
* Keystone Light, found with a blue label
* Keystone Ice, "ice brewed ale", found with a black label
Though Keystone and Keystone Premium exist, they are rare. The "Light" and "Ice" versions of the beer are far more prevalent and readily available for retail across the United States. Keystone Ice contains an alcohol content of 5.9% ABV, while Keystone and Keystone Premium have a cleaner, smoother taste than the other varieties. Keystone Light has an alcohol content 4.1% ABV.
A theory often thrown around the many college campuses where Keystone thrives as a cheap but drinkable party beer holds that cans of Keystone Light are simply relabeled Coors Light cans that have been found to be damaged in the manufacturing process.
Many amateur tests have shown that the vast majority of Keystone Light 12oz. cans do contain flaws while in comparison, the majority of 12oz Coors Light cans do not. Many also point to the similarities in beer taste, can shape, and inner liner as evidence that this theory may be true.
Given that the cans would have to be printed before they are filled, however, this is generally written off as an urban legend, and there is very little hard evidence that would suggest otherwise. For their part, Coors Brewing Company states that Keystone and Coors have separate brewing processes, so there is absolutely no validity to this rumor.