T D Gold & Collectables

Balas Ruby - Term used to describe a pale red variety of spinel.

Bloom - The frosted or matte surface on many types of gold jewellery, especially Victorian.

Bog Oak - Jet substitute made of peat preserved wood.

Bombe - Term used to describe a dome-shaped piece of jewellery

Calibre cut - gemstones that have been specially cut to fit with other stones in a setting.

Cannetille - extremely thin gold wire work decoration incorporating florettes and scrolls, used in France and England in the early C19^th

Carat - Unit for measuring the weight of gemstones or the fineness of gold Cabochon - Unfaceted domed cut with slightly convex or flat base used for heavily flawed stones or opaque stones such as opal and turquoise.

Carbuncle - term used to describe a Cabochon Almandine garnet.

Casseine - A type of plastic.

Champleve - Technique in which metal is stamped and the impressions filled with enamel.

Chelsea colour filter - Device used to identify gemstones. When a stone is viewed through a filter only deep red and yellow-green light is visible

Claws - Metal prongs that protrude from a setting to hold gemstones in place Closed back - Type of setting that in which the backs of gemstones are entirely covered in a metal backing

Cocktail Jewellery - name given to the chunky, polished gold jewellery of the late 1930’s and 1940’s

Cold enamel paint - Substance used to repair worn or damaged enamel, which is painted on cold rather than fired.

Collet setting - A type of setting in which a gemstone rests in a round band of metal.

Crown - Top half of a faceted gemstone.Culet - The bottom facet or point of a faceted gemstone

Cultured pearl - Pearl formed when a foreign body is placed in a mollusc by man

Demi-parure - A small set of matching jewellery usually a brooch and earrings

Doublet - Two layers of stone that have been glued together to resemble a single stone.

En tremblent - Type of setting in which the central cluster or part is spring mounted to produce a slightly trembling movement.

Facet - The surface plane of a cut gemstone

Fede ring - a ring featuring a design of clasped hands.

Foil - Metal sheet, often coloured, placed behind closed back gems to enhance colour or brilliance.

French jet - black glass used to imitate jet

Giardinetto jewellery - type of multi-coloured gem-set jewellery incorporating a floral design, fashionable in the C18^th .

Girdle - the circumference area around a gemstone, separating the crown from the pavilion.

Gletz marks - Type of inclusion found in white diamonds that appears as white cracks.

Gold Casing - Layer of gold encased around a base metal. Precursor to electroplate.

Granulation - Ancient technique in which tiny gold granules were applied to a gold surface.

Guilloche - An engine turned pattern engraved on a metal surface often covered in translucent enamel.

Hardstone - term covering a variety of opaque stones and semi-precious gems such as agate, onyx, bloodstone, carnelian etc.

Heat treated - Enhancement of the colour and clarity of gemstones by applying heat.

Horse tails - Wispy, fibrous inclusions occurring in demantoid garnets.

Inclusions - A visible internal flaw, usually taking the form of cracks, tiny pockets of gas or liquid, or foreign bodies.

Intaglio - Design carved or engraved into a stone.

Jade - Term covering both Jadeite and Nephrite

Matrix - Literally, Mother ; parent rock in which gemstones are found embedded .

Micro mosaic - Type of miniature mosaic made from pieces of coloured glass, produced in italy.

Milliegrain - Beaded metalwork used in jewellery settings.

Mitzpah - From the Hebrew for watch tower, implying “God watch over you” the word is featured in many pieces of sentimental jewellery.

Nacre - Iridescent coating produced by mollusc to form pearls

Negligee pendant - Pendant with two asymmetrical drops popular in the Edwardian period.

Oiled - Treatment which is given to Emeralds in which inclusions are filled with petroleum, rendering them invisible.

Open Back - A setting which gemstones are mounted on open metalwork so that light shines all the way through.

Orient - The lustre of pearl in Mother of pearl.

Oxidized silver - Silver treated to give it a blacken appearance.

Parure - A set of matching jewels, usually incorporating a necklace, earrings, brooch, bracelet and often a hair attachment.

Paste - Type of glass used to simulate gemstones.

Pavilion - bottom half of a faceted gemstone, below the girdle.Pforzheim - German jewellery making centre.

Pietra dura - Italian word for Hardstone, used particularly relation to Hardstone mosaics made in Florence.

Pinchbeck - Gold coloured alloy of copper and zinc used in C18^th and early C19^th.

Pique - Technique in which a material such as tortoiseshell is inlaid with metal decoration.

Plique-a-jour - Enamelling technique in which unbacked translucent enamel is supported by an openwork frame the principle being the same as stained glass.

Repousse - metalwork technique in which a relief design is pressed or punched out by hand or machine.

Rolled gold - An inexpensive substitute made by attaching a layer of gold to a base metal, which is the rolled out into sheets.

Sautoir - A long chain set with gemstones or pearls at intervals sometimes with a tassel.

Shakudo - Japanese metal work produce in the C19^th by former Samurai sword makers, in which copper, gold and silver were applied to steel plaquettes.

Shank - The hoop part of a ring that fits around the finger.

Shoulders - The sides of a ring flanking the central decoration or stone.

Soude emerald - A stone made by sandwiching a resign center between two slices of emerald.

Spanish Topaz - A erroneous name for certain types of citrine or Smokey quartz.

Strass stones - A type of lead-glass paste developed by Georges-Frederic Strass in the 1730’s.

Synthetic - Man made gemstone formed with the same chemical composition as a natural stone.

Table - The top facet of a cut gem stone.

Treated Diamonds - Diamonds that have been subjected to artificial radiation to enhance or change colour.

Vauxhall Glass - Type of mirrored or foil backed glass used to simulate gemstones in the C18^th and C19^th .