King of the Genii, famous for a golden cup full of the elixir of life. This cup, hidden by the genii, was discovered while digging the foundations of Persepolis.
I know too where the genii hid The jewelled cup of their king Jamshid, With life's elixir sparkling high.
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894
More on Jamshid' from Fact Monster: