If you have an unseasoned mortar and pestle or one made out of granite stone then you need to season it before using.
Care for granite mortar and pestle.
Ones made from wood and other rocks like granite may call for the same care as volcanic rock but ceramic types can be cleaned with soapy water.
This is because the porous surface can release particles of stone and grit into your food upon first use.
Seasoning preps the surface and removes any of these particles.
How you clean your mortar and pestle depends on the material it is made of.
Place the mortar on a stable work surface that will not crack under the pressure from pounding the mortar.
Clean ceramic glass and metal alloy brass iron mortar and.
To clean stone mortar and pestles made from marble granite or lava stone use warm water and rice.