Tools used to grind and crush substances into fine powders or pastes, Mortars are bowl-shaped containers and pestles are heavy, rod-shaped tools. Commonly sold as sets but also available separately, mortar and pestle sets may include mortars, pestles, adapters, housings, or other items in several materials.

Mortar and pestle implements have been used since ancient times to crush and grind substances. Mortars can be made of hard materials like wood, metal, ceramic, or hard stone such as granite or marble. Pestles are held in the hand and usually have a tapered, club-like shape. A wet or dry substance is placed in the mortar and the pestle is pressed against it and rotated until the material is pulverized.

What Is the Best Material for a Mortar and Pestle?
The implements must be made of materials that are hard enough to crush the substance without wearing away, but they cannot be brittle or break from the pressure of manipulation. The material should also be cohesive to reduce chipping and non-porous to avoid absorbing or trapping substances. Some rough porcelain mortars and pestles can reduce substances to very fine powders, but are brittle and stain more easily. Porcelain mortars can be pre-conditioned by grinding sand in them to produce a rougher surface. Glass mortars and pestles are stain-resistant and suitable for liquids, but are fragile and do not grind as finely as ceramic sets. Metal mortars and pestles are popular for food preparation.

Mortars and pestles are commonly used to grind and mix substances for dilution, to mask negative qualities, or to add volume to facilitate handling. Drugs can also be finely ground when not available in liquid form, and supplements can be processed to for addition to parenteral nutrition.