Watch List notes:

Italy, Norman Sicily. Roger II. 1105-1154. AV tari (13.06 mm, 1.50 g, 12 h). Palermo(?) mint, Third series, struck 1140-1154. Arabic legend reading al-malik Rujar al-mu'tazz billah / aroound central pellet, IC/XC NI/KA in two lines across field flanking central cross pattee; mint and date in outer margin. Spahr 63; MEC 206. EF, area of weak strike. 

This particular coin weighs as much as a Tremissis and would have roughly equaled 1/3 dinar (thus 1/3 Solidus or 1/3 Nomisma)