Artisanal casting
The first step in the creation of a piece of jewellery is obtaining the desired alloy with
specific percentages. In goldsmithing, the most frequently used metals are 925 silver, 375 gold (9 karat) or
750 gold (18 karat). The alloy is composed of the pure precious metal combines with other metals such as
copper, zinc and palladium. Different alloys with different karats have different colours, making white,
yellow or pink gold.
Each metal has its own melting point. To reach it, smelting is conducted in a fire-resistant crucible fired
by a gas torch. When the metal becomes liquid, it is poured into ingot moulds of different shapes (sheets or
wire) according to the design of the jewellery.
Lamination and wire drawing
Each metal has different characteristics. Gold is one of the most malleable and ductile metals.
It is possible to draw it as thin as a hair, or to laminate it between a pair of rollers to use it in sheets
for gold leafing and surface decorations.
The machinery used is the rolling mill, where a pair of rollers gradually narrows closer and closer together
to roll the metal into thinner and thinner plates, and the wire-drawing machine, where the metal is pulled
through plates with holes (draw dies) of decreasing diameter in several passes. The wire is pulled
mechanically or manually using pliers. Such processing phases require much time. The hardened metal must be
heated often with a flame, or it becomes too brittle because of multiple decreases of thickness, making it
susceptible to cracks and breakage.
The jeweller's workbench
The workbench is where the actual piece of jewellery is made using specific tools such as
pliers, drill, file, a bow-saw for fretwork or the removal of excess material, doming blocks and punches to
give concave shapes to sheets of metal, and different types of hammers and mallets in wood and rubber.
The bench is a solid wood structure with graduated drawers at different heights. Each has a specific
function. The highest is used to weld and heat the metal. It contains a fire-resistant plate. The next two
drawers contain tools, and are used to draw on paper or metal. The last drawer, the lowest and deepest, is
used to gather all offcuts and shavings of precious metal, which are preserved and melted down later.
The bench's worktop is used to affix clamps, lamps and the all-important bench pin or saddle, a small flat
wooden board with a V notch that is clamped in a vise or clamped to the workbench. This is used for the
filing, sawing and drilling of metal parts.
Once each component of the object is complete, the parts are welded together using a gas torch or a
micro-flame soldering unit, which is powerful and precise. Welding uses tha same alloy and colour as the
metal of the jewel, but with a lower fusion point. The jewel is then placed in a heated acid bath to remove
oxide created during the welding process. The piece is finished with files and sandpaper to eliminate excess
welding material and imperfections.
Mounting
Depending on the type of cut, the stone is mounted in a different setting. Agapanthus usually
sets the largest gemstones in straight-edge or scalloped-edge collets, which are made of thin strips of
metal moulded all around the edge of the stone.
For faceted gems, Agapanthus uses a claw setting. After an initial positioning of the metal, wires are fixed
with the graver to the outward face of the stone.
For jewellery adorned with tiny faceted gems, the surface of the piece is drilled directly where each stone
will sit. Using a graver, the gems are secured with bits of metal.
When many stones are set closely together using this technique, it is called a pavé setting. This augments
the piece's shimmer and creates continuity of the ornamental pattern of metal engraving.
Polishing, sanding and satining
The last step in the making of jewellery is the surface finish, which can be shiny, satined or sanded. The first two are done with a polishing machine. The final effect is achieved with abrasive paste and brushes of cotton or metal. Sanding requires a different machine, where air combines with sand to give the metal an all-matt surface.
Engraving
The metals at Agapanthus are engraved cold with gravers of different shapes according to the design. Engraving can be so light as to be considered a finish, or so deep and complex as to be a three-dimensional decoration.