The Philosopher’s Stone (note double-headed eagle in centre of diamond). See also Vajra (diamond, thunderbolt).
Double-Headed Eagle (The end product of the Magnum Opus). See also: Rebis in Alchemy, the divine Hermaphroditus (child of Hermes (Intellect) and Aphrodite (Feeling)), Ardanarishvara (androgynous form of Shiva merged with Parvati).