A Stonemason's Dictionary
A pocket dictionary of masonry terms, names and expressions

Caen Stone: Fine textured whitish limestone from Normandy.

Canpanile: A tower for housing bells.

Canopy: A small projecting roof above a door or other feature.

Cant Column: A column having a polygonal section.

Capital: A stone placed on the top of a column or pilaster to provide a larger load bearing upper surface. The capital usually being carved.

Carving Block: A squared off block left until last (when a piece of stone is being dressed) to accommodate a piece of carving to be added later. Sometimes carving blocks remain uncarved, for whatever reason, and can be seen on the finished building.

Caryatid: Columns carved in the form of humans.

Cathedral: The principal church of a diocese, containing the Cathedra, or Bishop’s throne.

Catherine Wheel Window: Circular window with radiating mullions.

Cauliflower: A derogatory term used to describe a badly made arch. When dressing voussoirs (the arch stones) there is a natural tendency to make them with too tight a radius, the resultant arch looks like a cauliflower!

Cavetto: A moulding whose hollow section is a quarter of an ellipse, or quadrant of a circle.

Celestory: Windows or opening set high in a wall above the roof of a side aisle.

Centering: The wooden frame which support arches and vaulting during construction.

Chad: A continuous row of chisel cuts angled into a flat surface.

Chain Block: A geared manually operated chain hoist with integral clutch.

Chamfer: A bevelled edge.

Chancel: The east end of the church, in which the alter is placed.

Chapter House: A room in which the chapter, or governing body of a Cathedral, meet.

Chase: A groove carved into a piece of masonry to receive lead flashing or similar.

Chevet: A form of apse in which the aisle continues round the end of the presbytery and has chapels radiating from it. Common in Europe.

Chevron: A Norman type of ornamentation formed by two deeply cut zig-zags.

Chick: Derogatory term for a slacker or shoddy worker.

Chilmark: Pale coloured limestone.

Choir: The part of the church occupied by the choir, often refers to the whole area east of the great screen.

Cinquefoil: A five petalled leaf form, as found in tracery.

Cinture: The ring at the top and bottom of a column, dividing it from the base and capital.

Claw Tool: A stonemason’s chisel with replaceable toothed bits for its cutting edge.

Cloister: A covered walkway around an open space.

Clustered Column: A column comprising several small shafts around a larger one.

Cock And Hens: Term (probably colloquial) for alternate tall and shallow coping stones on top of a wall.

Cock’s Comb: Variously profiled small plate steel tool with fine teeth for finishing fine limestone carvings.

Coffer: Recessed panel on the underside of a dome.

Colonade: A row of columns.

Column: A shaft, often round, octagonal, fluted or carved and usually having a base and capital, constructed to support a load.

Commode Step: The bottom step of a flight of steps, the end of the step being curved.

Conglomerate Stone: Rock composed of large rounded pebble like particles. Also called Pudding Stone.

Cope: Term applied to method of splitting stone.

Coping: Capping to a wall, to prevent rain soaking down from the top of the wall.

Corbel: A stone projecting from a wall to bear the weight of elements of the building such as floor joists or a protruding wall or parapet.

Corbel Table: The course of a wall which contains a row of corbels.

Cornice: The projecting moulding surmounting a section of wall.

Corona: The middle section of a cornice moulding, it has a vertical face and recessed horizontal soffit.

Crab: Hand wound winch used to hoist materials up scaffolding. The ones we used began their careers, I believe, winding barrage balloons up and down in World War 2, finally falling victim to health and safety regulations in 1980.

Cramp: Device (usually metal) for anchoring two stones together. Fixed using molten lead, or mortar.

Crenelation: Battlements on top of a wall.

Crick: A fissure through a block of stone, often invisible until the stone has been cut.

Crocket: Small bud like projections carved at regular intervals, often up the mitres of pinnacles

Crossing: The meeting point of the two transepts, the nave and chancel.

Crow’s Foot: A forked joggle.

Crypt: Chamber beneath a church

Cupola: A dome, usually refers to a small dome topped structure housing a bell.

Cusp: A pointed projection on the inside of an opening. Formed by the meeting of two smaller arcs joined to create an opening greater than the diameter of each.

Cutting one’s Throat: An expression used to describe the mistake of carving a moulding straight through, when it should have an internal return (angle) carved in. Once the throat has been cut, the stone is scrap.

Cyma Recta: A moulding of ogee section (wave-like).

Cyma Reversa: The same as above, but with the curvatures reversed.

Cymatium: Crowning member of a cornice.