Myth no more? I came across an interesting segment of text in my own search of information about the Philosopher's Stone that stated that, some centuries ago, an arabian alchemist managed to grow a red crystaline substance now classified as AuCI4 or gold tetrachloride dihydrate. The crystal was reported to be soluable and able to enrich other materials with gold, but only to the extent of the gold within the crystal.
I may be jumping the gun here, but if you take away all the myth and legend, doesn't this substance sound like a likely candidate for a REAL Philosopher's Stone?