THE BYZANTINE EMPIRE
JOHANNES II COMNENUS, 1118-1143
Mint of Constantinopolis
Electrum aspron trachy 1122-1143. Obv. Bust of Christ facing, with cross nimbus, wearing pallium and colobium, raising r. hand in benediction and holding book of Gospels in l. hand. On either side of nimbus, IC – XC. Rev. ω DECPOTH –  (GC wR GI). The Emperor, on l., and St. George on r., standing facing, holding a patriarchal cross on three steps. Sear 1942. DOC pl. 10, 3-4. 1.96 g. Scyphate form. Heavily clipped to ca. half weight. Extremely fine. Ex Auction Schenk-Behrens 67, Essen 1994, Lot650. Professoe Weiser gave following comment to the collector on May 5, 1994. Translated from the German version. ”This attractive specimen probably found its way to Sicily and was there ”modified” to the local monetary standard, however as ducale. This denominatiom was minted under Roger II (1105-1154) and William I (1154-1166) since 1140 in Palermo. (Spahr 72 or 94-99). Your thought that this specimen may have been part of the booty of the raid into Greece in 1147 and then brought to Palermo is highly captivating.

Update: Underweight because they were minted for use in Trebizond under Alexius I (1204-1222), see Prof. Dr. Andreas Sommer: Die Münzen des Byzantinischen Reiches 491-1453. Mit einem Anhang: Die Münzen des Reiches von Trapezunt. Regenstauf: Battenberg Verlag, 2010, S. 343 f., Nr. 61.2.2 u. 61.5 and passim.