BUILDING STONE...
Featured Glossary "B" Term

BACK ARCH: A concealed arch carrying the back lug of a wall where the exterior facing is carried by a lintel.

BACK FILLING: Rough masonry built behind a facing or between two faces. Or, filling over the extrados of an arch; brickwork in spaces between structural timbers, sometimes called brick nogging.

BACKING: The part of a veneer wall behind the exterior facing which is designed to resist load.

BACKING ROD: A flexible and compressible type of closed cell-foam polyethlene, butyl rubber, or open cell and closed cell polyurethane, rounded at surface to contact sealant. It is installed at the bottom or rear of joint and often described as a “filler strip”.

BACK-UP WALL: That part of masonry or other type wall behind the stone veneer, die, or facing.

BALUSTER: A miniature pillar or column supporting a rail usually used in balustrades.

BALUSTRADE: A railing or parapet consisting of a handrail and balusters, sometimes on a base member and sometimes interruptedby piers.

BANKER: A bench of timber or stone (may be a single block) on which stone is worked.

BASALT: A dense textured (aphanitic) igneous rock relatively high in iron and magnesia minerals and relatively low in silica, generally dark gray to black, and feldspathic. A general term in contradistinction to felsite, a light colored feldspathic and highly siliceous rock or similar texture and origin. The colors of basalts are very dark green to black and often sold as granites, but unlike granites, basalt contains little or no quartz or feldspars.

BASE: The bottom course of a stone wall, or the vertical first member above grade of a finished floor. Or, in a classical column, it is the part between the shaft and pedestal or paving.

BASE BLOCK: The squared block terminating a baseboard at the opening.

BASE COURSE: The lowest course, or footing of a wall or pier.

BASEBOARD: The skirting member at the junction of wall and floor. See base.

BASKETWEAVE: A checkerboard pattern in paving.

BAS-RELIEF: Sculpture or carving with slight projection from the background.

BAT: A piece of brick, usually half the size or smaller.

BATTED: Stone surface finish produced with parallel tool marks.

BATTER: Recessing or sloping masonry back in successive courses; the opposite of corbel.

BATTERED WALL: Inward slope from bottom to top of the face of a wall. Or, a term used by bricklayers and carpenters to signify a wall, piece of timber, or other materials, which do not stand upright; the opposite of corbel.

BATTING TOOL: A mason’s chisel several inches wide used to dress stone to a striated surface.

BEAD: The shape of a sealant in a joint after application.

BEAD JOINT: A joint with a half-round or half spherical section.

BEARING: A slot cut into the back of dimension stone to allow entry of a supporting angle or clip.

BEARING CHECK: A slot cut into the back of dimension stone to allow entry of a supporting angle or clip.

BED: The top or bottom of a joint, natural bedsurface of stone parallel to its stratification.

BED: In granites and marbles a layer or sheet of the rock mass that is horizontal, commonly curved and lenticular as developed by fractures. Sometimes applied also to the surface of parting between the sheets. Or, in stratified rocks the unit layer formed by sedimentation; of variable thickness and commonly tilted or distorted by subsequent deformation; generally develops a rock cleavage, parting or jointing along the planes of stratification.

BED JOINT: A horizontal joint between stones, usually filled with mortar, lead, or sealant.

BEDDING PLANE: Horizontal plane of sedimentary stone in the position of its original formation.

BELT COURSE: A continuous horizontal course of flat stones place in line marking a division in the wall plane. Sometimes called band course, string course, or sill course.

BENCH: Steps formed in quarry by removal of stone following bed joints. Or, a long seat of cubic stone.

BENCH MARK: A datum point from which differences in level are reckoned.

BERM: A bank of earth, such as the piled-up earth against a stone wall.

BEVEL: The angle that one surface or line makes with another, when they are not at right angles; a sloped surface contiguous with a vertical or horizontal surface.

BIOTITE: A black, brown, or dark-green mica, a magnesium iron silicate.

BIRD’S BEAK MOLDING: A drip mold found notably in the cap of the pilaster of the Doric order.

BLACK GRANITE: Dark colored igneous rocks defined by geologists as basalt, diabase, gabbro, diorite, and anorthosite, quarried as building stone, building facings, and specialty purposes and identified as Black Granite when sold.

BLEED: Staining action caused by corrosive metals, oil-based putties, mastics, caulking or sealing compounds. Rust-colored bleeding can also occur from stone that contains a high concentration of iron pyrite.

BLENDS: Mixes of different generic raw materials to form a water repellent.

BLENDING: Refers to the proper positioning of adjacent veneer panels, or floor slabs, or tiles by their predominant color to achieve an overall uniform pattern.

BLOCK: See Quarry Block.

BLOCKING: Internal members of wall furring or the like to afford fastening and rigidity for the veneer. Or, to fill a space within a shipping truck or container with fastened wood to prevent movement of stone.

BLUESTONE: A hard sandstone of characteristic blue, olive green, gray and buff colors quarried in the states of New York and Pennsylvania (historically quarried near the Hudson River, Appalachian Plateau). Bluestone is most commonly purchased for use as flagstone and other forms of paving.

BLUSHING: Film defect which appears as a milky opalescence as a clear coating or paint film dries.

BOLLARD: A free-standing stone post or guard. Or, a stone guard protecting a wall corner from damage by encroaching traffic.

BOND BREAKER: Normally in tape form. Used to ensure adhesion on both sides of the joint in joints of limited depth, and where a backing rod or other joint filler is not practical.

BOND COAT: An adhesive material used between the back of the stone tile or paver and the prepared surface.

BOND STONE: Used in varying percentages to anchor or bond the stone veneer to the backing material. Bond stones are generally cut to twice the bed thickness of the material being used. Or, stones projecting laterally into the backup wall used to tie the wall together.

BOOK MATCHING: Veneer slabs cut and assembled so that one slab will match the other in the horizontal direction, or in a vertical direction, but not both. Slabs must have alternate faces finished in sequence as they are layered in the quarry block.

BORDER: A flat stone used as an edging material, a border stone is generally used to retain the field of the terrace or platform.

BORDER STONE: Usually a flat stone used as a edging material. A border stone is generally used to retain the field of a terrace, platform, or floor.

BOSSAGE: A rough stone placed in a wall and projecting from it, that is left to be sculptured at a later time. Or, coursed stone ashlar with roughly dressed or projecting face.

BOULDERING: Paving with cobblestones.

BOULDERS: Boulders are heavy, rough stones commonly used in landscaping.

BREAK JOINTS: To arrange a course of stone so that its vertical joints are not in line with those of the course just below.

BREATHING: The passing of moisture in gaseous form through stone. Also called “vapor transmission.” To a greater or lesser extent all stone has this process occur.

BRECCIA: Marble or limestone in which angular fragments are imbedded in a matrix of the same of another composition.

BRECCIATED MARBLE: Any marble composed of angular fragments.

BRIDGE SAW: A saw that powers a circular diamond blade or blades which travel on a metal rail (bridge), and rests on supports. It is used to fabricate dimension stone slabs and cubic stone into square and rectangular pieces. Some models can be used to fabricate profiles and miters.

BROACH: To drill or cut out material left between closely spaced drill holes. Also, a mason’s sharp pointed chisel for dressing stone and a type of chisel used for working narrow surfaces.

BROKEN FLAGSTONE: Irregularly shaped stones, generally ½” to 2 ½” thick. See flagstone.

BROWNSTONE: A sandstone of characteristic brown or reddish-brown color that is due to a prominent amount of iron oxide as interstitial material. Or, a term applied to ferruginous dark brown and reddish brown askosic sandstones extensively used for construction in the U.S. during the 19th century Stone for New York City’s noted “brownstone fronts” came from the Connecticut Valley in Massachusetts, southeastern Pennsylvania, and New Jersey.

BRUSHED FINISH: Obtained by brushing the stone with a course rotary-type wire brush.

BTU: British Thermal Unit; the amount of heat required to raise the temperature of one pound of water one degree Fahrenheit at sea level, used as the basic unit of definite heat generation and transmission.

BUFFABLE: Capable of improvement in gloss or general appearance, or both, of a polish by a mechanical action.

BUGGED FINISH: A smooth finish produced by grinding with power sanders.

BUILDING STONE: Natural rock of adequate quality to be quarried and cut as dimension stone as it exists in nature.

BUILT-UP: Term indicating the assembly of pieces or layers to complete a wall, etc.

BULL NOSE: Convex rounding of a stone member, such as a stair tread. A convex, semicircular molding formed on the end of brick.

BUNDLE: A wooden framework in which large stone slabs are packed for shipment.

BURNISH FINISH: See polished finish.

BUSH HAMMERED: A mechanical process which produces textured surfaces. Textures vary from subtle to rough.

BUTTER/BUTTERING: To place mortar on a masonry unit with a trowel.

BUTT CRACK: Once thought to be exclusive to the plumbing trade, it is a visible sign of working with intense concentration and expertise.

BUTT JOINT: An external corner formed by the meeting of two square-edged stones, either one overlapping the other.

BUTTERING: Placing mortar on stone on stone tile units with a trowel before setting into position, to insure adhesion and to aid in leveling.

BUTTERBALL: A faulty method of installation which involves the use of spots of mortar at corners and middle of stone tile.

BUTTRESS: A projecting mass of masonry set at an angle to or bonded into a wall that it strengthens or supports. A buttress decreases in its cross-sectional area form top to base.

BUTYL: A synthetic rubber formed by the copolymerization of isobutylene and isoprene.

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