Do I need to season a granite mortar and pestle?

Yes, it would help if you seasoned a granite mortar and pestle. If you are using an unseasoned mortar and pestle or made of only granite/stone, you need to season it before using them. This is mainly because the porous substance can release particles of stones and grit into your food while using it for the first time. Seasoning makes a surface refined and removes all unnecessary particles from it.