The Collaborative International Dictionary of English v.0.48:

Xeriff \Xer"iff\ (z[e^]r"[i^]f), n. [See Shereef.]
   A gold coin formerly current in Egypt and Turkey, of the
   value of about 9s. 6d., or about $2.30 (ca. 1900); -- also,
   in Morocco, a ducat.
   [1913 Webster]