Rust resistant material. The mortar and pestle are made of 18/8 food grade stainless steel. Resistant to rust and damage and corrosion from acidic foods. - Strong and stable. Made of solid metal, the pestle provides a good grip and the mortar is stable. Padding on the bottom to stay in place. - Food grade. Stainless steel won’t retain residue or odors, just rinse under the tap for next use. - - Translucent lid lets you measure your strikes while keeping debris out out. - Suitable for all types of grinding. - Suitable for crushing medicines, herbs, spices, etc.