Alchemy: An Index of Possibilities is the second solo studio album by David Sylvian, first released in December 1985 on cassette only as a limited edition. Alchemy is an intermediary album, released between his first solo album Brilliant Trees and his next solo album Gone to Earth, made up of two entirely separate projects recorded 1984 and 1985.

David Sylvian is an English musician, singer and songwriter who came to prominence in the late 1970s as frontman and principal songwriter of the band Japan. The band's androgynous look and increasingly electronic sound made them an important influence on the UK's early-1980s New Romantic scene.