CABOCHON
A polished, not faceted, dome shaped stone – either round or oval with a flat polished base, primarily used as a cut for phenomenal stones such as cat’s eyes and stars.
CALIBRÉ
Calibré cut and invisibly set gemstones are techniques seen in antique jewellery in which gemstones were intricately fashioned by hand. To produce these exquisite techniques on an often minute scale, every facet and aspect of the stone required skilful and precise fashioning.
Calibré cut gemstones were worked into special shapes to fit into a specific area. Often calibré cuts fill a tapered row, encircle a stone, or create a flash of colour as a design element to a piece. Calibré cut stones can form a continual flow of colour due to the incredible channel settings in which they sit. Each gemstone would be fashioned so they sit right next to each other within a channel, with no metal in between visible from above. They would usually be held securely in place with a rubover or millegrain setting – a fine piece of secure metal bordering the stones. Calibré cut gems were usually faceted into small step-cuts or could also be polished to create tallow tops or miniature cabochons. Typical gemstones used were precious rubies, sapphires and emeralds, creating a burst of colour usually contrasted by bright diamonds.
CAMEO
The process of carving in order to leave a raised design (above the table of the stone) on a single piece of material. Cameos originated in ancient Greece, and at that time were exclusively made from hardstones, such as chalcedony. Antique cameos are rare and traditionally made from shell or stone. Modern copies are often made of plastic. The opposite of a cameo is an intaglio, which is carved into a material.
CARAT
In reference to gemstones, a unit of weight, abbreviated ‘ct’. 1 carat is equal to 0.2 grams.
In reference to gold, a unit of purity or fineness of gold and gold alloy, expressed as a number out of 24 parts by weight, e.g. ’24 carat’ signifies pure gold, ’18 carat’ 18/24th gold in the alloy, et cetera. Also abbreviated as ‘ct’.
Originally derived from the carob seed, called quirat in Arabic, a seed of naturally uniform weight.
CARTIER
Maison Cartier was founded in Paris in 1847 by Louis-François Cartier when he took over the workshop of his master. In 1874 his son, Alfred Cartier took over the company, but it was Alfred’s sons Louis, Pierre and Jacques, who were responsible for establishing the world-wide brand name of Cartier.
Louis assumed responsibility for the Paris branch, moving to the Rue de la Paix, in 1899. He was responsible for some of the company’s most celebrated designs, such as the mystery clocks, fashionable wristwatches and exotic Orientalist Art Deco designs, including the colourful “Tutti Frutti” jewels. Cartier also created the famous Panthère brooch of the 1940s for Wallis Simpson. Jacques took charge of the London operation and eventually moved to the current address at New Bond Street. Pierre Cartier established the New York City branch in 1909, moving in 1917 to the current location of 653 Fifth Avenue, the Neo-Renaissance mansion of Morton Freeman Plant which Cartier bought in exchange for $100 in cash and a double-stranded natural pearl necklace valued at the time at $1 million.
With a seemingly endless list of elite clientele, from kings to maharajas to Hollywood ‘royalty’, Cartier has since become synonymous with glamour and prestige.
CASTELLANI
Founded by Fortunato Pio Castellani (1794-1865) in 1816, the jewellery firm of Castellani is credited with popularizing Archaeological Revival style jewellery. Heavily influenced by the collection of ancient Greek and Etruscan jewellery of the Duke of Sermoneta, Fortunato focused of reviving ancient techniques, including granulation and filigree, in his jewellery. The Duke also contributed to Castellani’s business in his network of important international friends including Stendhal, Chateaubriand, Liszt and Balzac.
In 1851 Fortunato retired and left the business to his two sons, Alessandro (1823-1883) and Augusto (1829-1914). Augusto was the driving force rather than Alessandro, who had lost an arm in an accident was imprisoned for his political views and later was temporarily declared insane. He was then exiled and became the company’s foreign representative. They opened a London outlet on Frith Street in 1861 under the management of Carlo Giuliano, who was later to make his own name in the London jewellery industry. They later branched out into Christian symbolism, Byzantine-style micromosaic, and Renaissance revival jewels.
CEYLON
The island of Sri Lanka, formerly known as Ceylon is nicknamed the ‘Jewel box’ of the Indian Ocean, and has been recognised throughout history for its spectacular abundance and astonishing range of precious gemstones.
Despite being a small country, Sri Lanka is rich in a natural wealth of stones and has produced quantities of many types of gemstones such as garnet, moonstone, peridot, spinel and topaz but to name a few. Sri Lanka is however primarily known for its profusion of corundum gems, for example the prized phenomenal gems such as star sapphires, the rainbow hues of fancy colour sapphires, and notably the extraordinary and highly sought after padparadscha sapphires.
Of the most famous old mines, the Ceylon mines produced the largest quantity, as well as being the earliest source of sapphires in the world. Veddahs, the indigenous people of Ceylon, were the first people to come across the coloured pebbles in the sandy bottom of streams. From their discovery, the island became surrounded in myth and legend because of its treasure of beautiful, previously unheard of gemstones. One legend has it that King Solomon wooed the Queen of Sheba with jewellery set with Ceylon gemstones in 10th century BC. The island and its gems were even known to the Ancient Greeks and Egyptians and inspired the early 9th century ‘Arabian Nights’ tales.
Ceylon sapphires are celebrated for their bright mid blue colour, often referred to as a distinctive ‘cornflower’ blue hue. This attractive colour is typically a lighter shade of blue than sapphires from other mines across the world.
CHANNEL SET
A type of setting where by rows of gemstones are set next to each other and secured by metal borders to top and bottom, with no claws or beads used.
CHAUMET
The French jewellery house of Chaumet was founded by Marie-Etienne Nitot in Paris in the late eighteenth century. Among the first of Ninot’s dealings with the royal jewels of Europe was when he was asked to take inventory of the jewel collection of Marie-Antoinette. Over the next century, the firm would become the premier French jeweller, acting as the official jeweller to Napoleon I. Later in the nineteenth century the company came to be controlled by the Chaumet family, who continued this tradition of excellence, with patrons including the Tsars of Russia and the Shah of Persia, among many others. Today Chaumet’s flagship remains in the prestigious Place Vendome in Paris.
CHOPARD
Chopard were founded in 1860 in Switzerland by the expert watchmaker Louis-Ulysse Chopard. They were known for their high quality watches and were based in Geneva. In 1963 the company was sold to Karl Scheufele III who was a young goldsmith and watchmaker. He then introduced the jewellery segment to the company and in 1976 the first ‘Happy Diamonds’ watch was made. In the 1980s ‘Happy Diamonds’ jewellery pieces were created, for which they are well known.
CLAW SETTING
A claw setting is one in which the gemstone is secured via a number of metal ‘claws’ above the girdle of the stone, typically no less than four. This method was an innovation of the late nineteenth century, and most famously featured in the ‘Tiffany setting’ invented by the famed American jeweller Tiffany & Co in the 1880s. Prior to this gemstones were surrounded by a metal collet (or strip of metal formed around the girdle) which had the disadvantage of blocking light from passing through the gemstone.
CLUSTER
A grouping of gemstones, formed into a wide array of designs.
COCKTAIL RING
A type of finger ring invented in the second quarter of twentieth century that is not prescribed any particular form, but is typically large and set with various gemstones.
Cocktail rings were large enough so that they could not be worn under a glove, and thus were appropriate for more casual social occasions such as cocktail parties.
COLOMBIAN
Colombia is the source of the world’s finest emeralds. The mines of Colombia are situated in the eastern range of the Andes. The most famous of these are the Chivor and Muzo mines, known for high quality emeralds with a saturated pure green hue with bluish green overtones and a superior clarity. These mines were an ancient source of emeralds, first mined on an industrial scale by the Spanish in 1538.
CONCH PEARL
Conch pearls are formed inside the Queen Conch mollusk, a large sea snail, which lives primarily in the Caribbean Sea. Unlike true pearls, which are composed of nacre and derive from oysters or mussels, conch pearls are calcareous concretions with a porcelain-like surface.
Conch pearls are extremely rare. The most desirable specimen are orange or pink in colour and exhibit a distinctive flame structure which gives them the appearance of a burning fire on the surface.
CULTURED PEARL
Forced introduction of a bead nucleus into a mollusc, stimulating the animal to secrete layers of “nacre” over it, which forms a cultured pearl. Note, the use of the word “pearl” alone means “natural”. See “Natural Pearl”. Mohs hardness of 2.5
CURB CHAIN
Flattened, oval chain links.
CUSHION
Cushion cut diamonds are exceedingly beautiful and are found almost exclusively in antique jewellery.
When you see a cushion cut diamond, you immediately know that it was cut over 100 years ago and as such is one of the very earliest cuts of diamonds. The most usual shape of a natural rough diamond crystal- the octahedron- naturally lends itself to the cushion shape, with a rectangular or square outline with softly rounded corners.
Each cushion cut diamond displays unique irregularities in symmetry and proportions as each would have been cut by hand. Antique cushion cuts are known for their steeper crown facets, smaller tables, and larger culets. Every single cushion cut would have been cut to maximise the beauty of each individual diamond crystal, as opposed to modern day diamonds which are cut to retain as much diamond weight as possible. There is also a radical difference in cutting techniques, with modern diamonds being cut by laser machines, so that every single diamond has the same proportions. In contrast, cutting a diamond by hand was highly skilled work and extremely labour intensive, with no two cushion cuts looking identical.
Cushion were fashioned to look at their best in the lighting of the time- namely candlelight, gaslight and natural light. These diamonds have a completely different allure to more modern diamonds, with larger facets which create a particular sparkle made up of bright flashes of rainbow coloured ‘fire’. Queen Victoria was particularly enamoured with the beauty of diamond set jewellery, and decreed that diamonds should only be worn by married ladies- and only in the evening when their glitter would be best exhibited.A very rare cut of cushion shape diamonds is the ‘old mine’ cut. This cut is the very earliest form of cushion shape diamond. If you see an old mine cushion shape diamond, you know that the diamond would have originated from one of the first diamond sources ever discovered- namely India or Brazil. You do not see this cut from the abundant South African mines which were discovered in the late 1860s, the world leader in production of diamonds on the market continually to this day. Old mine diamonds typically have deep proportions and are slightly more irregular both in outline and arrangement of facets, scintillating with old world charm.