May you help me?

Composition: Alluminium
Diameter: 21 mm.
Weight: 0,85 gr.
Thickness 1,2 mm.
This coin is similar at 1/40 Imadi Riyal (y12a.1, y12a.2, y12.3) or at 1/80 Imadi Riyal (y11a), but it’s different in the marked points.
Thanks for your help