It is indeed a match to the Zeno coin. I initially thought your coin might be bronze and suggested as much before editing my original post. Some bronze alloys are "whitish". Cleaning and conservation can enhance that appearance.
Steve Album notes that more than 150 mints produced silver coins under Abu Sa'id.
There are aspects of the inscription that would be odd for silver generally but not completely unexpected in Anatolia, which is where my imagination went. The Zeno post mentions Lutz Ilisch, who is a leading authority. I'm confident now that it's a fals rather than a dirham or fraction.
Edited by Kushanshah
09/12/2019 1:05 pm