The Philosopher's Stone is a compilation album by Northern Irish singer-songwriter Van Morrison released in 1998.

The songs released on this 2-CD thirty-track album were previously unreleased outtakes from 1969 to 1988. The album features twenty-five songs that had never been released, and early alternative renditions of "The Street Only Knew Your Name" from Inarticulate Speech of the Heart, "Wonderful Remark" from The Best of Van Morrison, "Real Real Gone" from Enlightenment, "Joyous Sound" and "Flamingos Fly" from A Period of Transition, and "Bright Side of the Road" from Into the Music.

Three songs on the album were evidently intended for Morrison's unreleased 1975 album Mechanical Bliss. "Twilight Zone", "Foggy Mountain Top" and "Flamingos Fly" were all mixed in 1974 just before Mechanical Bliss was due to come out.