Albert Chain Gold or silver watch chain worn usually across a mans waistcoat from pocket to pocket with a watch attached at one end and maybe a key, seal or sovereign case at the other.
Amethyst Purple quartz.
Art Deco A decorative style that reached its height in the 1920's and 30's and emphasized abstract designs and geometric patterns.
Art Nouveau Art Nouveau, is a style of decoration from the 1890's and early 1900's. It was a style developed in protest against the mass-produced of wares and featured free flowing, curving asymmetrical lines with inspiration drawn from nature. 
Automata A moving mechanical device resembling a human being or animal to amuse and entertain.
Bar Brooch/Pin A brooch in the form of a horizontal bar with decoration along its length.  
Baroque Pearl A natural or cultured pearl of irregular shape formed within a pearl oyster that was used in jewellery to great effect in the late 16th century.
Beryl A mineral that includes several varieties of gemstones, especially Emerald and Aquamarine and various hues of yellow and pink. In its pure form Beryl is colourless. 
Bog Oak Black Oak preserved in Irish peat marshes and used in the Victorian era, as an inexpensive substitute for jet, in mourning jewellery.
Cabochon A gemstone cut in a smooth convex curve without facets.
Cairngorm A  yellow brown quartz stone originally found on Cairn Gorm in the Cairngorm mountain range in Scotland and typically used in Scottish pebble jewellery from the middle of the 19th century.
Cameo A form of carving a colour banded hard stone or shell in relief so that the subject stands out against a lighter or darker background.
Carnelian A red brown variety of chalcedony, a hard stone often carved in intaglio form as a seal.
Chatelaine A decorative hook worn from the waistband or belt from which were suspended a number of small, useful household items such as scissors, keys, etui, thimble case and even a watch. Typically carried by the housekeeper and made from precious and non-precious metals.
Citrine Yellow variety of quartz found mainly in Brazil.
Claddagh Ring  The Claddagh ring is a traditional Irish ring that represents love, loyalty and friendship. 
Corundum A mineral, aluminium oxide, the hardest mineral other than diamond, with a hardness of 9 on the Moh's scale. Corundum is seldom colourless and includes, blue, pink, green, yellow etc. Sapphire and Ruby are known as corundum
Cut Steel Articles of jewellery made of cut steel as studs or heads, faceted and pavé set to provide brilliance
Dress Clip  
Ecclesiastical Rings A type of finger ring worn and used by ecclesiastical or church dignitaries.
Edwardian The period of British history spanning the reign of King Edward VII, 1901 - 1910
Edwardian Jewellery Jewellery made during the reign of King Edward VII, 1901 - 10. The jewels tend to be lavishly decorated with gemstones, especially diamonds in very fine spindly settings. 
Electro-forming A technique where by an electric current deposits metal, usually gold ,silver or copper, into a resin mould enabling light weight copies of larger items to be produced. The crown made by Louis Osman for the investiture of Prince Charles in 1969 was made by this method.
Electro-plating A method of depositing a thin layer of gold or silver onto a base metal object using an electric current. It was developed in England in the 1840's by Elkington Bros, Birmingham.
Emerald Cut A style of cutting a gemstone to emphasize the colour rather than the brilliance of the stone.
Enamelling Powdered glass suspended in water is applied to a metal surface, such as gold or silver, and is then fired at a high temperature causing the glass to re-fuse leaving a smooth polished surface of varying colours, according to the metal oxide fired with the glass.
Eternity Ring A plain guard ring set all the way round with diamonds or gemstones , given as an anniversary present or for the birth of the first child.
Etruscan style A style of gold jewellery decorated with granulation or filigree.
Etui A small decorated case fitted with miniature tools such as scissors, needles, thimble, a tiny knife and maybe a pencil, often worn by a lady from a chatelaine.
Filigree An ancient decorative style on metal ware using fine wire, ( plain, twisted or plaited) forming delicate and intricate designs.
Fob A small ornament suspended from a watch chain. Fob originally refers to a small pocket in particular a mans small pocket in his trousers above the waistband.
French Jet Black glass jewellery imitating jet.
Fresh Water Pearl A pearl found in a mollusc from a river or fresh water lake.
Gilding Gold sheet beaten extremely thin is applied by heat or adhesive to an item made from a different base metal to give the appearance of gold.
Guard An antique long chain usually gold.
Guard Ring A plain ring usually worn in front of a more valuable ring to prevent its loss.
Gutta Percha A glutinous resin from trees found in Malaya used to make jewellery.
Gypsy Ring A wide gold ring with a diamond embedded into the metal so that the top of the stone is level with the surface of the metal. Often with an engraved star around the stone.
Hallmarks Marks struck onto gold and silver items, particularly in Great Britain, that attest the purity of the metal in accordance with legal requirements.
Hardstone Gemstones used to carve cameos and intaglios due to their strong and hard properties and opaque structure.
Intaglio A design cut down into the surface of a stone, opposite to a cameo, used to make seals.
Ivorine Celluloid or bakelite simulating ivory.
Jet A velvet-black substance formed from coal under extreme heat and pressure on ancient driftwood, the main source today being the shales of the Yorkshire coast near Whitby, England. Jet was used extensively in the manufacture of mourning jewellery, particularly after the death of Prince Albert in1861.
Keshi Non nucleated fresh water pearls, the original small piece of mantle inserted to start the process having dissolved before the pearl is completely formed.
Labradorite A type of feldspar originally found in Labrador, with a blue-green iridescence and often used in Art Nouveau jewellery.
Lapis Lazuli An opaque stone, deep-blue in colour, sometimes with specs of white or brassy-coloured pyrites. 
Lava Cameo A cameo carved in high relief from solidified porous ash (lava) usually from Mount Vesuvius in Italy, used extensively during the 19th century. The lava displays pale shades of grey and brown with a matt surface.
Luckenbooth A heart-shaped Scottish brooch (sometimes two hearts side by side) occasionally surmounted by a crown. They were often sold in the Luckenbooths, which were street stalls near St Giles Kirk, on the High Street in Edinburgh.  
Mabé Pearl A cultured blister pearl in a semi circular shape attached to the mantle of the oyster.
Marcasite Crystallised iron pyrites, an iron sulphide mineral used extensively in jewellery from the 18th century onwards, especially in France. The rose cut stones are generally pave set in silver to enhance their brilliance and were used in less expensive pieces as a substitute for diamonds.
Meershaum A whitish, soft clay like material which hardens when heated and used in Germany to make tobacco pipe bowls, cigar and cigarette holders as well as some carved ornamental items.
Mixed Cut A type of cutting used for gemstones incorporating a brilliant cut crown and a step cut pavilion.
Mohs' Scale A scale for measuring hardness of minerals and other hard substances, created in 1812 by the Austrian mineralogist Friedrich Mohs. 
Mother of Pearl The hard, smooth iridescent lining of the shell of certain large molluscs.
Nacre The iridescent material forming the outer layers of a pearl as well as mother of pearl.
Negligee A type of necklace with gemstones, pearls or paste often with a centered pendant with staggered drops.
Niello Work A process where by silver jewellery has an engraved design that is coloured black using an alloy of metallic sulphides. An ancient process made mainly in the far east today.
Onyx A type of chalcedony often with different striations of black, brown or white making it suitable for cutting as a cameo.
Orient The lustre of a pearl or mother of pearl.
Parure A matching suite of jewellery e.g. earrings, necklace and bracelet.
Paste Glass stones usually of great brilliance set into costume jewellery often with a coloured foil backing. Thought to derive from the Italian word pasta.
Pave Set Small stones set very close together in a piece of jewellery so that very little of the metal is visible.
Peridot An attractive transparent gem variety of olivine, a magnesium iron silicate  mineral which is found in basalts and peridotite rocks. 
Pietra Dura Hard stones used in flat slices in the type of mosaic made in Florence during the Renaissance and continuing today with small jewellery items.
Pinchbeck An alloy of copper and zinc developed by Christopher Pinchbeck to imitate gold in the 18th century, and used to make watch cases, jewellery and trinkets.
Pique A style of decoration of small luxury articles of tortoise shell. As tortoise shell is malleable when it is heated, small points or rods of metal are pushed into the heated shell. When the tortoise shell cools and hardens the points of metal are secured. 
Posy Holder A posy holder is a small funnel or trumpet shaped container made to hold a posy or nosegay of flowers that can be worn on a dress or jacket.
Rhinestone A term given to glass imitations of gems having a slightly iridescent effect.
Ruby Rubies have been held in high regard for centuries, especially in Asian countries where they adorned the armour of warriors and noblemen to make them invincible, in some cases even inserting them under the skin. The ruby’s blood red colour was thought to hold the power of life, and ancient Hindus offered them to their gods so that they would be reborn as emperors. Royalty and dynasties admired their perceived power and passion and rubies have even been buried beneath the foundations of new buildings to ensure good fortune. Read More ...
Sardonyx A banded variety of onyx, reddish-brown contrasting with white.
Scarab A talisman made originally in Egypt of a stylised dung beetle carved from steatite or gemstone and often set into jewellery.
Seal A devise that bears a monogram or design in intaglio to form an impress in relief in clay or wax. 
Spinel A gemstone found in a variety of colours
Sterling Silver An alloy of silver that has a fineness of 0.925 (92.5%) parts silver and 0.075 (7.5%) parts copper. 
Sweetmeat A small piece of sweet food, made of or covered in sugar. 
Synthetic Spinel  A stone that has been manufactured since the 1910
Translucent Allowing some light to pass through but not transparent.
Vermeil  Gilded silver, sterling silver covered with a layer of gold plating 
Victorian The period of British history spanning the reign of Queen Victoria from 1837 -1901.
Vulcanite A substance made from Indian rubber, can be moulded into jewellery to imitate jet. It is light weight warm to the touch and can be polished to a high sheen. 
Watch Balance Cock A wheel inside the pocket watch that is joined to the hairspring to regulate the speed of the watch, early ones were often intricately pierced and decorated.
Wedgwood Staffordshire potter Josiah Wedgwood who produced jasper ware often used in jewellery.