AR Dirham, 22 mm, 2.43g, Tabriz mint, AH 684/CE 1285-1286.
O: shahada in square, mint above.
R: Uighur inscription, with Arghun in Arabic at the bottom field.
This site provides an excellent intro to Ilkhan coins and how to read them if you don't already know how.
The Uighur inscription indicates that this coin has been struck under the authority of Arghun Khan. The Great Khan at this time who is unnamed here is Kublai Khan CE 1260-1294.