Glossary of Stone and Masonry Terms
A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
A-FRAME: A wooden or metal rack constructed in the shape of an "A" on which large stone slabs are shipped and stored.
ABATE: To cut away so as to leave parts in relief.
ABRASIVE FINISH: A flat non-reflective surface finish. Recommended for exterior use.
ABRASIVE HARDNESS (Ha): Refers to the wearing qualities of stone for floors, stair treads and similar uses subjected to abrasion by foot traffic.
ABRASION RESISTANCE: The property of a surface by which it resists being worn away as a result of friction.
ABSORPTION: Percentage of moisture absorption by weight. The process by which a liquid is taken into (soaked up by) another substance and held there. The weight of water a brick unit absorbs, when immersed in either cold or boiling water for a stated length of time, expressed as a percentage of weight of the dry unit.
ABUTMENT: The supporting wall or pier that receives the thrust of an arch; a solid stone springer at the lowest point of an arch, vault or beam.
ACCELERATOR: A material used to speed the setting of mortar, epoxy, and polyester resins.
ACRYLIC EMULSIONS: Clear water-based repellents which form a film. The acrylic resins come from the polymerization of derivatives of acrylic acids, including esters of acrylic acid, methacrylic acid, acrylonitrite, and their copolymers. Acrylics resins vary from hard brittle solids, to fibrous elastomeric structures to viscous liquids, depending on the monomer used and the method of polymerization.
ACRYLIC RESIN: See polyester resin.
ACRYLICS: Resins resulting from the polymerization of derivatives of acrylic acids including esters of acrylic acid, methacrylic acid, acrylonitrite, and their copolymers. They can be carried in a water or solvent solution and they are film-forming materials.
ACTIVE SOLIDS: Ingredients of a coating composition which are deposited following co-reaction or reaction with the substrate. Active solids are usually measured as a weight percent of the total.
ADHERED: Stone veneer secured and supported by adhesion of an approved bonding material over an approved backing.
ADHESIVE, ORGANIC: See mastic.
ADMIXTURES: Chemical additives included in the mixing batch for concrete manufacture or applied to the surface during the curing or setting process of the concrete, which variously accelerate or retard the curing time, provide coloring, waterproofing, tearing, special aggregate finishes fillers, etc…
ADOQUIN: A volcanic quartz-based stone containing a variety of colored aggregates and pumice in a quartz matrix. Quarried in Mexico and available in several colors.
AGATE: A variegated variety or quartz allowing colored bands or other markings (clouded, moss-like, etc…).
AGGLOMERATE: A man-made product fabricated to look like quarried stone. Usually composed of stone chips or fragments embedded in a matrix of mortar or thermosetting resins.
AGGREGATE: Materials that are added to mortar or grout at time of mixing to impart special properties to the mortar or grout; quantities of loose fragments of rock or mineral.
ALABASTER: A fine grained, translucent variety of gypsum, generally white in color. May be cut and carved easily with a knife or saw. The term is often incorrectly applied to fine-grained marble.
ALTAR: A table form; the center of most liturgical places of worship.
ALTAR RAIL: A railing across the chancel, or in front of the altar.
ALTARSCREEN: See reredos.
ALTERATION: Any project involving change of, or addition to, an existing building.
ALUMINA: Aluminum oxide.
ALUMINUM STEARATE: Complex salt or soap of aluminum and stearic acid. Used as a flattering and antisettling agent for pigments in paint and varnish, water repellents and cement additives.
AMBIENT TEMPERATURE: Temperature of the surrounding environment.
AMBO: One of the two pulpits or raised stands, usually stone, used in Christian churches.
ANCHOR: Metal device for securing dimensional stone to a structure or back-up walls.
ANCHORAGE: The means by which slabs are attached to a self-supporting structure.
ANCHORS: Types for stone work:
Of Flat Stone: Strap, cramps, dovetails, dowel strap, and dowel and two way anchors.
Corrugated: corrugated wall ties and dovetail anchors.
Round Stock: Rod cramp, rod anchor, eyebolt and dowel, flat hook, wall tie and dowel, dowel and wire toggle bolts.
ANGLE IRON: A structural steel angle; used for lintels to support masonry over openings, such as doors, windows or fireplaces.
ANHYDROUS: A hydrate which has given up all its previously held water molecules.
ANORTHOSITE: An usually dark-colored igneous rock consisting mostly or entirely of calcic plagioclase.
APEX: Top or peak of a pyramidal or conical form.
APEX STONE: Top stone of gable, spire, or pediment.
APRON: A trim piece under a projecting stone top, stool, etc…
ARAGONITE: A translucent white mineral found in calcium carbonate.
ARCADE: A range of arches with their supports; also, a passageway, one side of which is a range of arches supporting a roof.
ARCH: A curved stone structure resting on supports at both extremities used to sustain weight on bridge or roof on an open space. Or, a curved compression structural member, spanning openings or recesses; also built flat.
Back arch: A concealed arch carrying the backing of a wall where the exterior facing is carried by a lintel.
Jack arch: An arch having horizontal or nearly horizontal upper and lower surfaces. Also called a flat or straight arch.
Minor arch: Arch with maximum span of six feet and a rise to span with a ratio less than or equal to 0.15. Typically forms are jack arch, segmental arch, or multi-centered arch.
Relieving arch: An arch built over a lintel, flat arch, or smaller arch to divert loads,thus relieving the lower member from excessive loading. Also known as a discharging or safety arch.
Trimmer arch: An arch, usually a low rise arch of brick, used for supporting a fireplace hearth.
ARCHITECT: One skilled in the design of buildings and having technical knowledge of their construction.
ARCHITECTURE: The art and science of designing and constructing buildings adapted to their purposes, one which is beauty.
ARCHITRAVE: Member of an entablature resting on the capitals of columns and supporting the frieze.
ARCUATED CONSTRUCTION: Stone masonry in compression, using arch and vault.
AREA: The surface included within specific boundaries.
ARGILLITE: A compact metamorphic rock composed mainly of clay or shale, and aluminum silicate minerals. Similar to slate in appearance and splitting properties, but usually much harder.
ARKOSE, ARKOSIC SANDSTONE, FELDSPATHIC SANDSTONE: A quartz-based containing 10% or more of elastic grains or feldspar.
AROMATIC SOLVENTS: Hydrocarbon solvents comprised of organic compounds which contain an unsaturated ring of carbon atoms, including benzene, naphthalene and their derivatives.
ARTIFICIAL MARBLE: A man-made product that may look like natural quarried marble, sometimes composed of thermosetting resins as a matrix and fillers.
ARTIFICIAL STONE: A substitute for dimension stone made by casting selected aggregates and cement in molds.
ARRIS: The angle, corner, or edge produced by the meeting of two surfaces; the edge of external angle. A natural or applied line on the stone from which all the leveling and plumbing is measured.
ASHLAR: A flat faced surface generally square or rectangle having sawed or dressed beds and joints. Or, rectangular blocks having sawed planed, or rock-faced surface, contrasted with cut blocks which are accurately sized and surface tooled. May be laid in courses.
Coursed ashlar: ashlar set to form continuous horizontal joints.
Stacked ashlar: ashlar set to form continuous vertical joints.
Random ashlar: ashlar set with stones of varying length and height so that neither vertical nor horizontal joints are continuous.
ATRIUM: The open roofed entrance court of a building.
AXED: The surface finish produced by means of masonry axe tool.
AXIS: An imaginary line in plan or elevation dividing symmetrical parts.
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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 interrupted by 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.
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 argillaceous metamorphic sandstone of characteristic blue, gray and buff colors quarried in the states of New York and Pennsylvania (historically quarried near the Hudson River, Appalachian Plateau).
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: Tying various parts of masonry wall by lapping units on over another or by connecting with metal ties. Or, adhesion between mortar or grout and masonry units or reinforcement. Or, patterns formed by exposed faces of units.
American bond: A bond in which every sixth course is a header course and the intervening courses are stretcher courses.
Basket-weave bond: Module groups of brick laid at right angles to those adjacent.
Dutch cross bond: A bond consisting of alternate courses of stretchers and headers, with each stretcher centered on alternate headers in the courses above and below. Also called English bond.
Flemish bond: A bond consisting of courses made up of alternate stretchers and headers, with each header centered on a stretcher above and below.
Random bond: Masonry constructed without a regular pattern.
Running bond: A bond in which units in successive courses are placed so they overlap. Placing vertical mortar joints centered over the unit below is called a center or half bond, while lapping one-third of the way is called a third bond and one-fourth of the way is called a quarter bond. Some building codes require at least a quarter bond to qualify as running bond.
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: Heavy, rough stones.
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 textures 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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CALCARENITE: Limestone composed predominantly of clastic sand-size grains of calcite, or rarely aragonic, usually as fragments of shells or fossils. Some calcarenites contain oolites and may be termed oolitic limestone. Calareous quart-based stone in which the calcium carbonate is present chiefly as binding material are not included in this category.
CALCAREOUS: Calcium-bearing rock.
CALCITE: The natural mineral form of calcium carbonate.
CALCITE LIMESTONE: A limestone containing not more than 5% of magnesium carbonate.
CALCITE MARBLE: A crystalline variety of limestone containing not more than 5% of magnesium carbonate.
CALCITE STREAKS: Descriptions of a white or milky-like streak occurring in stone. It is a joint plane usually wider than a glass seam and has been re-cemented by deposition of calcite in the crack and is structurally sound.
CALCIUM OXIDE: Calcined limestone.
CAMBER: A slight rising from the horizontal, to gain an actual or apparent effect of arching.
CANOPY: A sheltering roof over a niche or a doorway.
CANTERA: A volcanic quartz-based stone with qualities similar to Adoquin, but not as dense; quarried in Mexico.
CANTILEVER: A structural member, supported at only one end, that projects from a wall.
CAP: Masonry units laid on top of a finished wall, column, door, or molding.
CAPACITY INSULATION: The ability of masonry to store heat as a result of its mass, density and specific heat.
CAPILLARY ACTION: The movement of a liquid in the interstices of a porous material, as a result of surface tension; the phenomenon responsible for dry materials sucking moisture above the normal water level.
CAPITAL: Column cap, the top member or group of members of a column, pier, shaft, or pilaster.
CAPPING: See coping..
CAPSTONE: The crowning stone of a structure; differing from capital in that it is not a supporting member.
CARBONATE: A salt of carbonic acid.
CARBONIC ACID: A weak acid.
CARVE: Shaping by cutting a design to form; the trade of a sculptor.
CARVER: In the stone industry, the artisan who does carved work.
CARVING: Cutting of ornamental shapes, figures, etc… from models or details, which are too intricate to produce from patterns.
CAST STONE: A precast concrete building stone manufactured to simulate dimension stone.
CATALYST: A substance which accelerates a chemical reaction but appears to remain unchanged itself (i.e. a hardener that accelerates the cure of synthetic resin adhesive).
CAULK: A non-staining, non-hardening putty-like mastic, usually applied to stone joints with a pressure gun.
CAULKING: The application of a sealant in a joint or opening to prevent the passage of water, air, dust, and noise. Or, making a joint tight or leak proof by sealing with an elastic adhesive compound.
CAVITY VENT: An opening in joints of veneer to allow the passage of air and moisture from the wall cavity to the exterior.
CAVITY WALL: An exterior wall, usually of masonry, consisting of an outer and inner wythe separated by continuous airspace.
C/B RATIO: The ratio of the weight of water absorbed by a masonry unit when immersed 24 hours in cold water to the weight of water absorbed after an additional immersion for five hours in boiling water. Also called the saturation coefficient.
CELL: Cells are distinguished from core holes by being larger in size.
CEMENT: A hydraulic mixture, without aggregate, consisting of a calcined mixture of clay and pulverized limestone.
CEMENT PUTTY/CREAM/BUTTER: A thick, creamy mixture made with pore cement and water which is used to strengthen the bond between the stone and the setting bed.
CEMENTITIOUS: Made from, or composed of, portland cement.
CENTERING: Temporary formwork for the support of masonry arches or lintels during construction. Also called center (s).
CHAMFER: To bevel the junction of an exterior angle. Or, to cut away the edge where two surfaces meet in an external angle, leaving a bevel at the junction.
CHANCEL: That part of a church interior reserved for clergy and containing the alter.
CHASE: A continuous recess in a wall to receive pipes, ducts, conduit, etc….
CHAT SAWED: Description of a textured stone finish, obtained by using chat sand in the gang sawing process.
CHAT SAWN FINISH: A rough gang saw finish produced by sawing with course chat.
CHECK: A rebate, normally larger than a fillet.
CHECKER WORK: Masonry of square-face stones not breaking joints.
CHIMNEY: A shaft, approximately vertical, which helps create a draft for conducting the smoke and gases of combustion from above a fire to the outside.
CHIMNEY BREAST: The exterior face of the wall directly above the fireplace opening.
CHIMNEY LINING: Fire clay, terra cotta, or refractory cement built inside a chimney.
CHIMNEY THROAT: That part of a chimney directly above the firebox where the walls are brought close together.
CHIP: A small, irregularly shaped stone piece dislodged, usually from the edge, from a stone piece.
CIRCULAR CIRCULAR FACE: A stone face worked to convex spherical shape.
CIRCULAR CIRCULAR SUNK FACE: A stone face worked to concave spherical shape.
CIRCUALAR SAW: Machine with power-driven revolving steel disc, rimmed with diamond or other abrasive elements.
CIRCUALAR FACE: A stone face worked to convex circular (not spherical) shape.
CIRCULAR SUNK FACE: A stone face worked to a concave circular (not spherical) shape.
CLADDING: An exterior veneer stone covering that is non-load bearing.
CLASTIC: Stone fragments that are derived from pre-existing rocks or minerals.
CLASS OF UNIT: A ranking of masonry units according to their different grades or types in ASTM specifications, the different raw materials they are manufactured from, or other characteristics.
CLAW TOOL: Toothed chisel used in roughing out process.
CLAY: A natural mineral aggregate consisting essentially of hydrous aluminum silicate. It is plastic when sufficiently wetted, stiff when dried, and vitrified when fired to a sufficiently high temperature.
CLAY MORTAR: A soft, low lime mortar usually used when lime was expensive and difficult to procure. Its primary usage was in remote areas for small scale buildings.
CLEAN BACK: The visible end of a stone laid as a bond stone.
CLEANING: The removal of marks, dust, and other extraneous materials from the surface of the stone.
CLEANOUT HOLES: Openings at the bottom of a grout space for cleaning mortar droppings and other debris prior to grout placement.
CLEAR COATING: An invisible to glossy film or penetrate applied to substrates to protect, repel or resist water and hydration of minerals.
CLEARANCE: Space allowed to facilitate erection of units and provide for thermal and other estimated movements in structure.
CLEAVAGE: The ability of a rock mass to break along natural surfaces; a surface of natural parting. Also used to refer to the plane or planes along which a stone may likely break or delaminate.
CLEAVAGE MEMBRANE: Membrane that provides a separation and slip sheet between the mortar setting bed and the backing or base surface.
CLEAVAGE PLANE: Plane or planes along which a stone may likely break or delaminate.
CLOSER: The last masonry unit or portion of a unit laid in a course.
CLOSURE: Supplementary or short length units used at corners or jambs to maintain bond patterns.
COATING: A protective or decorative covering applied to the surface or impregnated into stone for such purposes as waterproofing, enhancing resistance to weathering, wear, and chemical action, or altering the appearance of the stone.
COBBLESTONE: A natural rounded stone large enough for use in paving.
CODE: Legal restrictions of a given locality governing the building of various types of structures.
COLLAR JOINT: The vertical longitudinal joint between wythes of masonry filled with mortar or grout.
COLUMN: An isolated vertical member whose horizontal dimension measured at right angles to the thickness does not exceed three times its thickness and whose height is at least three times its thickness.
COMMERCIAL MARBLE: A crystalline rock composed predominately of one or more of the following minerals: calcite, dolomite, or serpentine, and capable of taking a polish.
COMPOSITE: A construction unit in which stone that is to be exposed in the final use is permanently bonded or joined to concealed material.
COMPOSITE ACTION: Transfer of stress between components of a member designed so that in resisting loads, the combined components act together as a single member.
COMPOSITE MASONRY: Multi-component masonry members acting with composite action.
CONCRETE: A composition material consisting of Portland Cement, aggregate, and water. When mixed together, will result in a chemical action that will set and harden into rock-like mass.
CONCRETE MASONRY UNIT: A masonry unit made of Portland Cement, water, and mineral aggregates, formed into a rectangular prism.
CONDENSATION: Dampness of interior surfaces caused by the release of water as it cools below the dew point; the formation of frost or water when air carrying water vapor comes in contact with a cold surface, cooling the air and reducing its ability to hold moisture.
CONGLOMERATE: A stone similar to sandstone but the rock particles are rounded or angular gravel rather than sand; an aggregate of rounded and water-worn pebbles and boulders cemented together into a coherent stone.
CONSOLIDATION: Treatment of the stone surface with a liquid solution which is commonly brush or spray applied; various stone consolidation processes can extend the life of stone and retard the decay process, but they cannot permanently arrest deterioration. Consolidation techniques employ both organic and inorganic chemicals. Inorganic processes have long-life and exhibit similar expansion-contraction behavior as treated material. Most inorganic processes cannot reattach loose pieces of stone or fill gaps in large cracks; adhesives may be required for the purposes. Organic processes are based on the use of synthetic resins. Their life span is generally less than that of inorganic material, but they can be especially effective with porous stone as well as comprehensive strengths. Epoxy resins, for example, are good adhesives and weatherizers, but current available epoxies are sensitive to ultraviolet rays which tend to discolor in time and do not weather well. Mixtures and combinations of both organic and inorganic treatments such as ethyl silicate are continually being developed to take advantage of the benefits of both treatments.
CONTAINER: An enclosed truck body that is usually used to hold and carry imported dimension stone into the United States.
CONTOUR SCALING: A crust forming across the surface of sandstones and limestones which follows the contour of the surface rather than the bedding planes of the stones; the result of direct pollution; the pores of the stone are blocked by formations of recrystallized calcium sulfates.
CONTRACTION JOINTS: Spaces where panels are joined and which expand as the panels contract.
CONTRACTOR: One who erects and installs fabricated dimensional stone.
CONTROL JOINT: Provision for the dimensional change of different parts of a structure due to shrinkage, expansion, temperature variation or other causes, so as to avoid the development of high stresses.
COPE STONE: The horizontal top stone of a wall or similar stone construction , usually flat.
COPING: A cap or covering course on top of masonry wall. Designed to shed water, protect the top and provide a finished, closed appearance to the wall. Commonly extended beyond the wall face and incorporating a drip. SEC: Single edge coping; DEC: Double edge coping.
COQUINA: Limestone composed predominately of shells or fragments of shells loosely cemented by calcite. Coquina is course-textured and has a high porosity. The term is applied principally to a very porous rock quarried in Florida.
CORAL LIMESTONE: A limestone consisting of the calcareous skeletons of corals, often containing fragments of other organisms and usually cemented by calcium carbonate.
CORBEL: Projecting successive courses of masonry out from the face of the wall to increase the wall thickness or to form a shelf or ledge.
CORBEL PLATES: Concealed plates of nonferrous metal fixed into a structure to support stone cladding at intervals and over openings.
CORE: Continuous openings or perforations within extruded clay products.
CORNERSTONE: A stone forming a part of a corner or angle in a wall. Also a stone laid at the formal inauguration of the erection of a building.
CORNICE: A molded projecting stone at the top of an entablature or facade.
CORROSION RESISTANT: Steel items which have been treated or coated to retard harmful oxidation or other corrosive action.
COUNTERSINK: An added depression below a surface, as to receive the head of a nail, screw, or bolt; also, the sinkage of a small area below the surface plane.
COURSE: A continuous horizontal band of stone of constant height.
COURSED VENEER: This is achieved by using stones of the same or approximately the same heights. Horizontal joints runs on the entire length of the veneered area. Vertical joints are constantly broken so that no two joints will be over one another.
COUSSINET: French for the stone at the top of a pier supporting the lowest stone of an arch.
COVE BASE: A concave stone molding.
COVE JOINT: A concave joint shaped with a tool.
CRACK: A break, split, fracture, fissure, separation, cleavage, or elongated narrow opening, however caused, visible without magnification to the human eye and extending from the surface into the stone, through the grain, matrix, or vein.
CRAMP: A ‘U’ shaped metal anchor for holding two adjacent units of stone together.
CRANDALL: A multi-pointed hammer for dressing the face of stone.
CRATE: A wooden protective case in which stone is packed for shipment.
CRATERING: Depression in a coating film usually caused by air or solvent trapped in the coating, forming bubbles which break after the film has set sufficiently to prevent leveling.
CRAZING, CRAZE, CRACK: Fine, random cracks or fissures in a network on or under a surface of plaster, cement, mortar, concrete, ceramic coating or paint film; caused by shrinkage.
CREEP: The permanent and continuing dimensional deformation of material under a sustained load, following the initial spontaneous plastic deformation. In structures particularly concrete, the permanent deflection of structural framing or structural decking resulting from plastic flow under continued stress. In roofing, the permanent elongation or shrinkage of roofing membrane, resulting from thermal or moisture changes.
CROSS-BEDDING: The arrangements of laminations of strata transverse or oblique to the main planes of stratification.
CROSSETTE: (Croissette, Crosset) A side lug at the upper side of an arch stone, entering a corresponding space on the adjoining stone.
CROWFOOT VEIN: (Stylolite) Description of a dark gray to black zigzag marking occurring in stone; usually structurally sound.
CROSS-SECTIONAL AREA: The area of a particular portion of a member or the area of a masonry unit.
Gross cross-sectional area: The area delineated by the out-to-out dimensions of masonry or a masonry unit in the plane under construction.
Net cross-sectional area: The net cross-sectional area of a masonry unit is the gross cross-sectional area minus the area of the cores or cells. For brick units cored less than 25% the net area is equal to the gross area. Or, the area of masonry units, grout, and mortar crossed by the plane under consideration based on out-to-out dimensions.
CRYSTALLINE LIMESTONE: Limestone, either calcite or dolomite, composed of interlocking crystalline grains of the constituent minerals and of phaneritic texture. Commonly used synonymous with marble, and thus representing a recrystallized limestone. Improperly applied to limestones that display some obviously crystalline grains in a fine-grained mass but which are not of interlocking texture and do not compose the entire mass. (NOTE: All limestones are microscopically, or in part megascopically, crystalline; the term is thus confusing but should be restricted to stones that are completely crystalline and of megascopic and interlocking texture and that may be classed as marbles.)