Technical Terms Jewellery

Alloy a mixture of various metals, like when base metals are added to silver to make it stronger. Sterling silver is 92.5% pure silver and it is usually mixed with copper.

Annealing a process where silver is heated and then quickly cooled again. This way the metal will be softer and more pliable. This term is also used for the slow cooling of glass to prevent inner tension that could lead to a fracture when the glass has cooled.

Baroque Pearls irregularly shaped pearls.

Belle Époque ('Beautiful Era') an overly decorative style which was fashionable from the 19th century until the First World War.

Branded Silver a mark on an object which indicates that it is made of Sterling Silver.

Cabochon a polished but unfaceted gemstone that is often impure.

Cameo gemstones, coral, lava or seashells that were engraved in such a way that the image is set off by contrasting colours in the background. A cameo usually depicts a bust or a face that is positioned en profil.

Carat a unit of mass for gemstones. One carat equals 200 mg. The same name is also used to indicate the purity of gold. 24 carat gold is pure gold.

Champlevé ('heightened field') a technique where the troughs and cells in a metal surface are filled with enamel.

Cloisonné a technique that is used for decorating metal objects. Compartments (cloisons) are added to the metalwork by welding on thin wires that are filled with enamel later on.

Diamond Engravings a means of decorating glass. A motif is etched into an item's surface with the help of engraving cutters.

Dot technique a glass decoration technique where small hammers with steel or diamond tips are used to create a pattern of dots on the glass' surface.

Engraving decorative patterns which have been etched into a metal surface with a sharp object.

Faceted a sloping edge around a mirror, window or gemstone that has been cut into shape.

Faceting a technique where facets are cut into a metal surface so the light will be reflected. It was a very popular technique during the neo-classicist period.

Favrile iridescent glass that contains metal oxides. It was developed by Louis Comfort Tiffany.

Filigree metalwork that looks like lace. It is made of gold and silver threads of metal and it might incorporate beading as well.

Genève-enamel enamel painted on a metal surface. This technique is generally used for decorative plaques in jewellery.

Gilding a method where silver, ceramics or glass is covered with a thin layer of gold.

Guilloché colourless enamel that has been applied on a metal surface which was engraved (either by hand or with the help of a rotating machine). This makes the enamel look like watery silk.

Inclusions natural flaws within gemstones.

Intaglio a method of decorating stone and glass by engraving an image deeply into the surface.

Iridescent glass glass that has a pearl coating due to its exposure to acids.

Jade a Chinese, green, decorative stone that is fairly easy to shape.

Lead glass this specific kind of glass was discovered around 1676. It has a high percentage of plumbous oxide which is why the glass has such a remarkable shine to it.

Matrix the material in which gemstones are embedded. These stones are typically used in Arts and Crafts jewellery and in Art Nouveau jewellery.

Matting creating a matte surface by pouring acid onto metal or by hammering a dense pattern into the metal surface.

Meander a decorative border based on ancient Greek examples.

Metal spinning technique used by silversmiths; an object is shaped by pressing it around a rotating metal spool. This technique is mostly used to create round items.

Mourning jewels sets of jewels that has been made specifically for times of mourning. Even though their origins are older, the most famous example of mourning jewels is the 19th century, jet jewellery. It became fashionable after the death of Prince Albert, Queen Victoria's husband, in 1861.

Oeil de perdrix ('eye of the partridge') an enamel or gilded pattern of dotted circles. This technique was already introduced in Sèvres' porcelain factory before 1770.

Parure a matching set of jewellery that exists of a necklace, earrings and a brooch.

Patina the colouring of a wooden or metal surface that has aged, worn or been treated with chemicals.

Pavé a technique where gemstones are set so close to each other that the surface is not visible anymore.

Pearl edge a decorative edge of densely set pearls that has been cast, applied or reprocessed.

Pietra Dura colourful stones which are used in the decoration of furniture and jewellery. Its most famous centre was in Florence.

Plate this term was originally used by the English as a name for silver dishware. Nowadays, it is used for silver-plated objects.

Plique-à-jour enamel is poured into a shape that has many compartments. The result virtually looks the same as stained glass windows.

Precious Coral ever since ancient times, red coral (Corallum rubrum) is frequently used in jewellery. This type of marine coral comes from the Mediterranean Sea.

Repoussé a technique where a metal object is hammered from the back as well as the front to make the motif stand out more.

Savonette a watch with a glass cover that partly exposes the clock's face.

Shakudo an alloy of copper and gold that is used in Japanese ironwork.

Shibuichi an alloy of copper and silver that is used in Japanese ironwork.

Sterling silver the English term for silver that has a purity of at least 92.5%.

Tinfoil thinly rolled tin that is used for mirrors or that is placed underneath gemstones to improve the piece's brightness.