Mats
From EncyclopAtys
Mats (MP in French) means raw material. It can be drilling elements, cut up (looted during a hunt) or OP mats (which arrive in the GH, when it has a Outpost) or you can buy them to Merchants (in dapper, in Elyps, and/or Guild points). You can even receive gifts (on events) or when playing to the Wheel of fortune.
There's different level and type: since Patch 00837 (December 2020) stars show if it's basic (no star), fine (1 star), choice (2 stars), excellent (3) or Supreme (4).