The glossary includes definitions of terms used in the captions, and offers a general vocabulary useful in referring to the materials.
Metal. A member of a group of materials that are conductors of electricity and heat, usually malleable, capable of being hammered thin, fusible, and that exhibit some luster. Base metals are aluminum, copper, iron, lead, nickel, tin, and zinc.
Alloys include brass, bronze, pewter, gar-alloy, steel, and nickel silver. Precious metals are gold, silver, and platinum.

Metal finishes. The final surface textures of the material, produced by mechanical means or as a result of the normal production process. Metal finishes include as-fabricated, buffed, directional textured, nondirectional textured, and patterned. See individual entries.

Metal leaf. Very thin sheets of metal (they can be 0.000004 inch) applied to the surface of metal, wood, plaster, or glass, usually used for decorative purposes. Also called foil.

Mexican paver tile. Handmade terra-cotta tile used for floors. The tile is very porous, and must be sealed to be practical. Also called Mexican floor tile.

Mirror finish. See As-fabricated, Buffed finish.

Miter. The junction of two units at an angle, usually 45 degrees.

Modular brick. Brick made to fit within a module, usually 4 or 8 inches, which forms the base unit of modular brick construction. In the United States, the nominal dimensions are 4 x 22&Mac218;3 x 8 inches (dimensions given are width, height, length). Closure or econo, 4 x 4 x 8 inches. Engineer, 4 x 31&Mac218;2 x 8 inches. Utility, 4 x 4 x 12 inches. Norman, 4 x 22&Mac218;3 x 12 inches. Roman, 4 x 2 x 12 inches. Ancient roman brick is the same general proportion (although the height is often relatively smaller), but may be a variety of specific dimensions. See also Nonmodular brick.

Molded brick. (1) Hand-molded brick is made by pressing soft clay into a two-part mold dusted with sand (which remains on the surface after firing) or water as a release. (2) Sand-struck brick is made by a mechanized process in which wet clay, known as “soft mud,” is forced into a mold using sand as a release. Different colored sands are used for various effects.
(3) Water-struck brick is made by a mechanized process and uses water as a release, resulting in a smooth finished surface.

Molded glass. Glass shaped by a variety of techniques, including pouring molten glass into a mold, allowing a hot plastic sheet of glass to slump into a mold or to sag around a form, and making impressions in hot, plastic glass.

Molding. A shaped member, usually ornamental, used to accent an architectural or decorative element or to conceal construction joinings and intersections. Commonly used moldings are illustrated in figures G-5 and G-6.
Monolithic concrete. Concrete building units cast with no joints.
Mortar. (1) A plastic mixture usually consisting of portland cement paste, lime, and sand. (2) Any cementitious aggregate.