Mortar (building material, mortar and pestle, and weapon)

Building mortar: composition, types and use

Masonry mortar typically contains a binder (lime, gypsum or Portland cement), fine aggregate (usually sand) and water; modern mixes may include plasticizers, pigments or air-entraining agents. Types range from soft lime mortars, prized for compatibility with historic masonry, to stronger cement-based mortars used in contemporary construction. Mortars are selected for workability, compressive strength, permeability and color matching.

• Common types: non-hydraulic lime mortar, hydraulic lime, cementitious mortar, gypsum and clay mortars.
• Applications: bedding bricks and stones, repointing joints, plastering and rendering.
• Techniques: mixing proportions, joint tooling, curing and protection from frost and rapid drying affect durability.

Conservation and distinctions

In conservation work, compatibility of porosity and flexibility is essential; hard cement mortars can damage softer historic masonry by trapping moisture or causing differential stress. Mortar differs from concrete (larger aggregate and structural use) and grout (fluid mixes for filling voids). Appropriate selection and sacrificial repair mortars help preserve heritage fabric.

Mortar and pestle: tool, materials and uses

The mortar (a bowl) and pestle (a club-shaped grinder) is among the oldest tools for reducing solids by grinding, pounding and mixing. Materials for mortars and pestles include granite, marble, porcelain, wood and metal; choice depends on hardness, porosity and potential chemical interaction. They remain valuable where tactile control of particle size and texture matters, for preparing spices, medicines, pigments and small laboratory samples. Cleaning and avoiding cross-contamination are important in culinary and pharmaceutical use.

Mortar (weapon): design, ammunition and role

As an artillery weapon, a mortar is designed to launch projectiles at a steep arc to reach targets behind cover or within trenches. Typical components include the tube, baseplate and sighting or aiming gear; light infantry mortars are man-portable while heavier systems require vehicles or emplacements. Mortar ammunition commonly includes high-explosive, smoke, illumination and practice rounds; modern developments include guided or precision munitions in some forces. Mortars provide indirect, relatively portable fire support and are valued for simplicity, rapid deployment and the ability to engage defilade positions.

Safety considerations

Safety issues vary by meaning: in construction, silicate dust and additives require dust control and respiratory protection; in conservation, proper testing prevents chemical damage; with mortar and pestle, hygienic cleaning prevents contamination; in military contexts, handling and firing munitions demand strict procedures, hearing and eye protection and ordnance safety protocols.

Summary

Whether as a bonding paste, a grinding implement, or an artillery piece, the various meanings of "mortar" reflect practical technologies for shaping, combining or delivering material. Understanding the material properties, historical context and safe practices for each interpretation helps in selection, use and preservation.