"Blue Sky" (also known as Big Blue or Blue Magic) is the street name which has been coined for the notoriously potent and 99.1% chemically pure crystal methamphetamine that Walter White and Jesse Pinkman manufacture. The name comes from the distinctive light blue coloration of the meth crystals, a result of the chemical formula Walt devised to get around sales restrictions on pseudoephedrine. Amongst the steps, the process creates phenylacetone (from phenylacetic acid) in a tube furnace charged with a thorium oxide catalyst, followed with reductive amination (methylamine and aluminum amalgam) to yield methamphetamine.

The blue color is apparently a plot device, introduced by the show's writers to make Walt's product visually identifiable. Although blue methamphetamine, sometimes called "smurf dope ," exists in the real world, 100% pure methamphetamine would appear as colorless/white crystals. Furthermore, Walt's phenylacetone/methylamine synthesis would yield a less-desirable racemic mixture of d- and l- methamphetamine. Generally d-methamphetamine is considered preferable to a racemic mixture of d and l-methamphetamine. This is because l-methamphetamine has a very low affinity for dopamine receptors, the receptors that give amphetamines their pleasurable effects, to the point where pure l-methamphetamine is sold over the counter as a decongestant. It is possible that Walt's process is chirally selective, which would produce nearly 100% d-methamphetamine. This phenylacetone method was once popular with the outlaw biker gangs in the 1960s and 1970s, but faded away once phenylacetic acid and methylamine became watched as drug precursor chemicals by the DEA. The synthesis of methamphetamine is now typically done through the reduction of ephedrine or pseudoephedrine, using either hydriodic acid and red phosphorus or lithium metal dissolved in anhydrous ammonia. The reduction of pseudoephedrine produces only d-methamphetamine.

Originally distributed solely in Albuquerque by Jesse's street dealers, the drug has spread across the Southwest due to the efforts of Gus Fring, a major dealer in the region. Purchasing Walt and Jesse's surplus of 38 pounds, Gus uses his Los Pollos Hermanos franchise to distribute the meth to the surrounding states of Arizona, Texas and Nevada. Since then, Gus has become the sole supplier of the product, recruiting Walt and Jesse to produce a quota of at least 200 pounds a week in a "superlab" underneath an industrial laundromat owned by Fring.

The blue meth has even made its way south of the border into the country of Mexico, attracting the attention of the local drug cartels in the area, particularly, the Juárez Cartel, as described in the song "Negro y Azul: The Ballad of Heisenberg," ("Negro y Azul").

Background Information and NotesEdit

• Blue Sky makes a split-second cameo appearance in the AMC series The Walking Dead, in the episode titled "Bloodletting". It can briefly be seen in Merle Dixon's drug stash which contains crystal meth among other drugs.
• Blue Sky props consist of crystalyzed sugar and are essentially pieces of blue rock candy.