Techniques
One of the stages when making jewelry. The metal mount in which the stone will be set is carefully pierced so as to expose the pavilion (the lower part) of the stone. This operation allows light to pass through the stone and, in doing so, increases its lustre.
To give a final, polished finish to an item of jewelry. Buffing is performed either by hand or using a lathe fitted with abrasive discs, brushes and bits.
The technique of decorating the surface of a metal using small chisels and hammers. Unlike engraving, the metal is not cut but indented. Chasing, along with embossing, is the oldest decorative technique developed by man.
Chemical decomposition of certain substances produced by an electrical current. It is applied in galvanoplasty to gild, silver- or chromium-plate an object or jewel.
Operation whereby transparent colored enamel (in the form of ground glass) is melted over an engraved or guilloché surface.
The edge separating the pavilion and the crown of a cut stone other than a diamond. It can be more or less narrow, rough or polished.
As its etymology suggests (from the Greek gluptos meaning “engraved”), glyptic is the art of engraving precious, colored or decorative stones. Seals and intaglios are hollowed, while cameos are carved in relief. The art of glyptic appeared in Mesopotamia towards the fifth millennium BC in the form of seals and the first cylinder-seals. The Egyptians gave magnificent
expression to this technique with amulets engraved in emeralds or stones such as turquoise, lapis-lazuli and amethyst. Greeks and the Romans created superb intaglios and cameos whose quality remained unsurpassed until the Renaissance period in Italy and France.
This casting technique, the origins of which have been lost in the mists of time, is used to produce small sculpted objects in metal (gold, silver, bronze, copper, brass, etc.). Traditionally, a hollow wax figure of the object is modeled then encased in clay, the innermost layer of which closely follows the shape of the object. A hole is made at the top and bottom of the mould. The mold is baked to melt the wax, which runs out of the hole in the base. The molten metal is then poured through the hole in the top. Once cold, the clay mold is broken, revealing the object in metal. The sculpture is then filed to refine the surface, cleaned and polished.
A life-size representation in wax or plastiline of an artist’s drawing of a piece of jewelry. The function of the model is to provide the most accurate representation possible of the finished piece and assess the end result.
The action of removing marks left on precious metals by tools. This operation prepares the metals for buffing.
A technique whereby an object is polished using a series of increasingly gentle abrasives to give a smooth, even and shiny finish. Polishing is a profession in its own right, requiring many years of experience.
One of the stages when making jewelry. The jeweler marks the metal with the shape of the stone to be set, then pierces the metal and positions the stone in order to ensure the outline is accurate. The next stage is the "A jour" technique.
The art of setting, in other words to secure a gem in a mount, is one of the jeweler’s most noble tasks as the stone must be set in such a way as to best show off its qualities. Generally speaking there are three main types of settings: closed setting, prong, pavé or bead setting, and invisible setting.The closed setting is the oldest and most secure method of setting a stone. A thin strip of metal is folded around the stone’s girdle or rondiste. The stone is therefore completely enclosed in metal.
Prong, pavé and bead settings are more modern styles in which more of the stone is exposed, allowing a maximum amount of light to enter the stone, thus increasing its attractiveness. In the prong setting, tiny metal prongs (or claws, hence the alternative name of “claw setting”) attached to the gallery of the mount are bent over the table of the stone. In the peg setting, these prongs are replaced by thin gold wires whose tip is shaped like the head of a nail. In the pavé setting, the stone is secured by tiny shavings of metal, lifted from around the metal mount. It takes three to six prongs, and three or four beads to set a stone.In the third method, the invisible setting, the mount disappears from view to reveal the full luster of the stone.
This style of setting requires special preparation of the stone, which must be cut in an angular shape, and is only suitable when setting several stones side by side in a pavé. V-shaped notches are cut into the pavilion (the bottom part of the stone). Each stone is then “snapped” tightly into a metal rail, and slid along until it sits snugly beside its neighbor.All that remains is a very thin wire of gold around the pavé. The invisible setting was invented and patented by Cartier in 1933.
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