Medieval Silver Coin Italy?

I acquired this coin at a coin show in Fort Worth yesterday.
The obverse legend appears to be: PRIMASEDSES
The reverse legend appears to be: GALLIAR

It is silver, and is 19mm in diameter.

http://www.elfreeman2.com/t18/18t098r.jpg

http://www.elfreeman2.com/t18/18t098o.jpg

I am not good with Biaggi, and it is too early for Krause catalogs (probably 1200-1600). Googling the obverse legend implied it was related to Palermo.

Can anyone assist in identifying this one?

https://fr.numista.com/catalogue/pieces41342.html

Thank you for your help; that really narrowed the search!

I had not weighed the coin; it is 1.1 grams by my scale (which is accurate to +/- 0.1 gram. Following the links from the listing you sent, mine appears to be the denier fort or 2 deniers (PDA 5032 or thereabouts).

The following coin shows a weight of about 0.8 gram, but the Numis Corner listings all showed weights of 1.1 grams or so:

https://en.numista.com/catalogue/pieces57178.html

Hello
I am interested, do you want to swap it ?

A trade is possible, depending upon value and what you have to trade.
I have sent you a personal message.