C. (cable moulding - cyma reversa)

Cable moulding: moulding in the form of a strand of rope.

Caission: a sunken panel.

Calcareous (material): material containing chalk or other forms of calcium carbonate or lime.

Calcination: in this context the conversion of carbonate to lime.

Calcium oxide: CaO, commonly called quicklime.

Camber: an upward curve or slope in a beam or lintel. A camber arch is one which tends to be flat.

Canopy: an ornamental projection over windows, doorways, niches, etc.

Cant: an obtuse angle.

Cantilever: a term often used to describe a form of projecting bracket.

Capital: the head or top part of a column or pilaster.

Carbonation, carbonated: a lime plaster is said to have carbonated when the binder has reacted with carbon dioxide from the air and developed strength beyond that which is achieved simply by drying out.

Carton Pierre: an old method used to produce fine casts of ornament, it consisted of paper pulp, glue size and whiting mixed to a dough like consistency then pressed into plaster moulds.

Case: a plaster frame to keep various parts of a mould in position - casement: a wide, shallow moulding.

Casein: a protein in milk with many industrial applications including glue making. It can form an adhesive with lime.

Cast: an object produced from a mould.

Cast in fibrous plaster: a relatively thin coat of plaster 203 mm thick, reinforced by wooden members, laths, etc, and Hessian canvas; finally, a further thin coat of plaster often termed firstings and seconds.

Cavetto: a round concave hollow moulding containing the quadrant of a circle. Often found in a cornice.

Cement: In this context a quick-setting binder for making mortars and concretes. By far the most widespread cement is the Portland Cement (OPC) formed by grinding a clinker which has been prepared at high kiln temperatures from a mixture of clay and limestone. There are, however, other forms of cement including ënatural cementsí formed from naturally occurring nodules of calcareous clay (such as Septaria). A distinction between these and other hydraulic limes is that cements must be ground to a fine powder before they can slake.

Chalk: a common form of calcium carbonate with a very fine structure. A limestone, cretaceous in age, usually very porous and fine-grained ranging from white to pale grey in colour.

Chamfer: a bevelled face.

Chaplet: a moulding containing pearls or rosettes.

Checquer: a pattern formed of alternate squares.

Chord: a line in a circle connecting the two ends or springing of a circle or arch.

Cinque foil: a trio-leaved flower used in the arches of the lights and tracery of windows and external panelling.

Clay: a term given to hydrous silicates of aluminia generally deriving from the decomposition of earlier rocks.  Examples are slate clay, fire clay, plastic clay, china or porcelain clay and common clay or loam.

Coarse Stuff: a mixture of lime putty and aggregate which is stored to mature for use as a plaster or render (1st and 2nd coats).

Coat: a layer or thickness of plaster or render done at one time.

Coffer: a recessed or sunken panel often found in ceilings, soffits, domes or vaults.

Collar: a plaster band or bands that will provide the correct outline for a plaster to use as grounds when forming columns in plaster or other mixes.

Colonade: a row of columns.

Column: a vertical pillar or shaft, usually supported off a base and crowned with a capital. A column can be circular, oval or square in section; smooth or fluted. In classical design, the dimensions and ornamentation of a column will vary depending upon the appropriate classical order.

Concave: a rounded or circular hollow. The opposite to convex.

Concrete: a structural building material which can be cast in fluid state but will set to a firm solid. It consists of sands and stones with water and a binder such as cement or hydraulic lime. This differs from mortar in containing much larger aggregate sizes.

Console: a bracket supporting the cornice over a window or doorway.

Coved: an arched recess - a concave moulding.

Convex: rising in a circular form - opposite of concave.

Corbel: a projection jutting out from the face of a wall, usually to support the weight of a structure or ornament above.

Core (of a wall): in some forms of masonry construction the walls are built with carefully set facing units on the two faces, and the space between these is filled with a rubble concrete which is known as the core.

Core: the inner portion of a column or other large component onto which plaster/render is run. The core is provided to save materials and weight.

Cornice: a projection made up of several members which finishes or crowns an entablature or wall.

Corona: the top edge of a cornice projecting over the bed-moulding designed to throw off water often termed the drip or weathering.

Counter laths: spacing laths running behind and at right angles to the main laths which carry the plaster. This may be to even up the surface, or to allow a space for the nibs to form a key when the plaster is pressed through.

Crenelle: a parapet or cornice with battlements or loopholes.

Cross screeds: The secondary screeds which run between, and at right angles to, the main screeds in defining the plane of a carefully ruled plaster surface.

Cure (to cure): The setting and hardening process of a plastic mix containing a cementitious binder.

Curing: the hardening of a material by time in a natural manner.

Cusp: one of a series of points projecting form the soffit or mouldings of an arch, giving a trefoil or multifoil form in the arch.

Cyma recta: is a moulding which is concave at the top and convex at the bottom.

Cyma reversa: is a moulding which is convex at the top and concave at the bottom. Often also called an Ogee moulding.
 
 

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