on the Elixir of Langgan Efflorescence, from the Purple Texts Inscribed by the Spirits of Grand Tenuity". This text was originally part of the Daoist Shangqing School scriptural corpus supposedly revealed to Yang Xi (330-c. 386 CE) between 364 and 370. The Purple Texts alchemical recipe for preparing Elixir of Langgan Efflorescence involves nine steps in four stages carried out over thirteen years. The first stage produces the Langgan Efflorescence proper, which when ingested is said to make "one's complexion similar to gold and jade and enables one to summon divine beings". The next three stages further refine and transform the Langgan Elixir, repeatedly plant it in the earth, and eventually generate a tree whose fruits confer immortality when eaten, just like those of the legendary langgan tree on Mount Kunlun. Upon completing any of the nine successive steps in producing the elixir, the alchemist (or adept in the neidan interpretation) can choose to either ingest the products and obtain immortality by ascending into the realm of Shangqing heavens or may continue on to the next step with the promise of ever-increasing rewards. The first stage has one complex waidan step of compounding the primary Langgan Efflorescence. After performing ritual zhāi 齋 "purification practices" for 40 days, the adept spends 60 days to acquire and prepared the elixir's fourteen ingredients, place them in a crucible, add mercury on top of them, lute the crucible with several layers of mud, and after sacrificing wine to the divinities, heating the crucible for 100 days. The elixir's fourteen reagents, given in exalted code names such as "White-Silk Flying Dragon" for quartz, are: cinnabar, realgar, milky quartz, azurite, amethyst, graphite, saltpeter, sulfur, asbestos, mica, iron pyrite, lead carbonate, Turkestan salt (desert lake precipitates containing gypsum, anhydrite, and halite), and orpiment. Based upon these ingredients, Schafer says the end product was probably bluish flint glass with a high lead content. The alchemist can either leave the crucible closed and proceed to the next stage or break it open and consume the langan elixir that is said to yield marvelous results. The efflorescence should have thirty-seven hues. It is a volatile liquid both brilliant and mottled, a purple aurora darkly flashing. This is called the Elixir of Langgan Efflorescence. If, just at dawn on the first day of the eleventh, fourth, or eighth month, you bow repeatedly and ingest one ounce of this elixir with the