Silver, 10 mm, 0.38 g
First of all, I checked sa'adian and Interegnum coins...nothing similar to this bad quality coin.
The one I found a little bit similar is an Almoravid 1/2 qirat like A-468 or maybe 1/4 or 1/8 qirat due to the small weight.
I have Vives and Brethes but it's not easy to compare the arabic writing with above photos...
Thanks