C. (calcined plaster - carton pierre)
 

Calcined plaster - Another name for calcium sulphate, hemihydrate.  See plaster of Paris.
Museum of Fine Arts, Boston (2000)

Calcite - The most common crystalline form of calcium carbonate. Calcite is widely distributed throughout the world as chalk, limestone, and marble. Iceland is famous for producing large clear calcite crystals that are used in optical systems (Iceland spar). In addition to clear colourless crystals, calcite may also appear white or pale shades of other colours depending on the crystal size and the presence of impurities. Marble is limestone that has been metamorphosed to form compact crystals of calcite. Calcite has been gathered or mined since Paleolithic times. In the form of chalk, calcite was powdered for use as a pigment. It is the main raw material used in the manufacture of Portland  cement.  Limestone and marble are used for sculpture and buildings.
Museum of Fine Arts, Boston (2000); RS Means Building Glossary (undated)

Calcite limestone - A limestone that does not contain any more than 5% magnesium carbonate (Grimmer 1984).
Museum of Fine Arts, Boston (2000)

Calcium aluminate cement -   A combination of calcium carbonate and aluminates that have  been thermally fused or sintered and ground to make cement. 
RS Means Building Glossary (undated)

Calcium carbonate  CaCO₃ -  A white powder that can occur in three crystalline forms: calcite (hexagonal-rhombohedral), aragonite (orthorhombic) and vaterite. Calcium carbonate occurs naturally in many forms such as chalk, limestone, marble and sea shells. It can be found world-wide and ranges in colour (because of impurities) from white to grey to yellow. A white pigment of calcium carbonate is prepared by grinding limestone, chalk or shells with water then using levigation to separate the coarser material. Artificial chalk, also known as precipitated chalk, is whiter and more homogeneous than natural chalk. Pearl white is made from calcined oyster shells.
Synonyms: chalk; calcite (Eng., Fr., It.); calcita (Sp.); aragonite; pearl white; oystershell white; marble; limestone, whiting; lime white; marl; travertine; Pigment White 18; white earth; English white; Paris white; drop chalk
Museum of Fine Arts, Boston (2000)

Calcium hydroxide Ca(OH)₂  - A soft, white, alkaline powder. Calcium hydroxide, or slaked lime, is made by grinding quicklime (calcium oxide) with water; this forms a fine-grained precipitate. Calcium hydroxide absorbs carbon dioxide from the air forming calcium carbonate. It is used as a component in hydraulic cements because it will set underwater. Calcium hydroxide is also used, as a preservative in water paints. A saturated solution of calcium hydroxide, called limewater, has a pH of 12.4.
Synonyms: slaked lime; calcium hydrate; lime hydrate; caustic lime; limewater
Museum of Fine Arts, Boston (2000)

Calcium oxide - White, alkaline lumps. Calcium oxide is a refractory solid that becomes incandescent at temperatures near its melting point (2500°C). Calcium oxide is primarily used in the manufacture of slaked limes for mortar, plasters and cements. 
Synonyms: lime; quicklime; burnt lime; calx; unslaked lime; fluxing lime
Museum of Fine Arts, Boston (2000)

Calcium sulphate CaSO₄ -  Commonly found in three forms: anhydrous (anhydrite), dihydrate (gypsum) and hemihydrate (plaster of Paris). Anhydrite is a colourless, inert pigment which is often used as a paper filler. Calcium sulphate dihydrate is used in the manufacture of Portland cement. Gypsum is also used as a filler and pigment in paints, enamels, glazes and paper. Plaster of Paris is used for wall plaster, wallboard, mouldings and statuary.
Synonyms: anhydrite; gypsum; plaster; terra alba; alabaster; calcium sulphate; mineral white; crown filler; alabastine; pearl filler
Museum of Fine Arts, Boston (2000)

Calcium sulphate, anhydrous  CaSO₄ -  White, odourless crystals whose mineral form is called anhydrite. Anhydrous calcium sulphate is ground to form a colourless, inert pigment. 
Synonyms: anhydrite; karstenite; muriacite; anhydrous sulphate of lime; anhydrous gypsum; 
Museum of Fine Arts, Boston (2000)

Calcium sulphate, hemihydrate  CaSO₄-0.5H2O  - Fine-grained, odourless powder. Plaster of Paris is made by partially calcining gypsum. When mixed with water, plaster of Paris will dry to a hard mass. It is used for wall plasters, wallboard, mouldings and statuary.  See plaster of Paris.
Synonyms: plaster of Paris; dried calcium sulphate; dried gypsum; plaster
Museum of Fine Arts, Boston (2000)

Candelilla wax - A yellowish-brown vegetable wax exuded from the leaves and stems of succulent shrubs, Euphorbia antisyphilitica and Pedilanthus pavinia, native to northern Mexico and the south-western U.S. Candelilla wax is obtained by boiling the leaves and stems in water and sulphuric acid. Candelilla is composed of hydrocarbons, centred around C31 with smaller amounts of esters and triterpenoids. It is a dark brown wax that is hard and brittle with little tack. Candelilla wax is an all-purpose wax used for polishes, cements, Ebonite varnishes, waterproofing, metal casting and insect-proofing.
Synonyms: candilla wax (sp.); Stralpitz [Strahl & Pitsch]
Museum of Fine Arts, Boston (2000)

Caput mortuum - An obsolete name for a reddish-brown pigment prepared by calcining red iron oxide. It is listed among the pigments used for colouring stucco marble in the nineteenth and twentieth century. In the twentieth century, polishing-red (iron oxide, caput mortuum; English red) was mentioned as one type of polish introduced. It could be mixed into a polishing wax.
Wittenburg (1999); Museum of Fine Arts, Boston (2000)

Carbonate of lime - Common name for calcium carbonate prior to the 1800's when chemical compound names were standardised (Schur 1985).
Synonyms: calcium carbonate
Museum of Fine Arts, Boston (2000)

Carborundum - A brand name for any of several artificial abrasives made from silicon carbide, fused alumina and other materials. Edward Atcheson accidentally made Carborundum in 1884 when he was attempting to synthesise diamonds. He incorrectly assumed his new product contained carbon and aluminium and hence trademarked the name Carborundum as a variant of corundum. His product was, however, composed of silicon carbide which has a Mohs hardness value of 9.17. Now many varieties of Carborundum are available with varying hardness and grit. 
Synonyms: silicon carbide
Museum of Fine Arts, Boston (2000)

Carnauba wax - A hard, yellowish vegetable wax exuded from the leaves of the palm tree, Copernicia cerifera, native to the arid regions of north-eastern Brazil. The leaves are collected, dried then beaten to remove the wax surface coating. The wax is melted, filtered and bleached with fuller's earth or charcoal. Carnauba wax is harder than beeswax and melts at a higher temperature. Carnauba wax contains ceryl palmitate, myricyl ceretate, myricyl alcohol (C30H61OH) along with other high molecular weight esters and alcohols. Olho wax is a pure whitish grey carnauba wax obtained from young leaves. Refined olho wax is called flora wax. Palha wax is a brownish wax obtained from older leaves. Palha wax can be emulsified with water to form chalky wax. Carnauba is used in varnishes. For stucco marble, wax treatment often followed the application of oil to the surface in order to increase the gloss of an already well polished surface. In these cases carnauba wax  was often used, applied to the surface with a linen cloth.
Synonyms: Brazil wax; ceara wax; olho wax; flora wax; pahla wax; chalky wax
Wittenburg (1999); Museum of Fine Arts, Boston (2000)

Carpenter's glue - Usually a skin or bone glue. See animal glue.
Museum of Fine Arts, Boston (2000)

Carton-Pierre  -  This was made from pulped paper with glue and whiting added, and found considerable decorative use, mainly in the 18th and 19th centuries, in the form of applied architectural decoration, candelabra and statuary.
Ashurst (1983)
 

Bibliography              Index