Saudi Arabian Silver Riyal

Scans often tend to eliminate the appearance of mint lustre due to the flat lighting.
The detail of this type of coin gives good protection to the fields beneath, so if there are any tiny nicks present, the best place to look for them is in the script.
The constant height of the script leaves very few prominent points in the relief for wear to be concentrated. Consequently, the best place to look for wear is in the palm trees and the swords. It is a bit hard to see wear in these features with the scan, the best thing to do is examine these with a powerful magnifing glass.

A USB microscope would provide good pictures to enable us grade this coin properly. A good USB microscope can be bought in the $50 to $100 range, and would provide a magnification range from 1:1 to 200:1.

My guess for a grade from these pictures would be EF to Uncirculated.

Handsome looking coin.

I agree wit sel_69l, the coin is about AU to UNC. It is fairly common, with 60 million being minted in AH1354. Anyway, you did great buying it for under $10, that means you only paid melt value for it (maybe even a little below). I would estimate its value at about $20, but if it grades UNC, then you are looking at $25-$30.

It really is a beautiful coin, I have one dated 1370.