Terminology: Jewellery & Silversmithing

 
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A quick run down of terms frequently used around the workshop.

Alloy

The term used for a mixed metal. For example, sterling silver is an alloy because typically it is a mix of fine silver and copper where as fine silver is not an alloy, it is pure silver. Alloying is the term used to describe the process of mixing metals to create another. For example, alloying fine silver with copper to make sterling silver. You can read more about the differences of sterling silver and fine silver in our blog post 925 Silver vs 999 Silver.

Annealing

Is a process of heat treating metal to a predetermined temperature which alters the properties of the material to increase its workability and reduce its hardness. Metals such as silver, copper and brass can be left to air cool or quenched into water. Setting up your annealing and soldering areas in a darker corner of your workshop helps you to see the colour changes in the metal as it is heated.

Anti Clastic Raising

A metal forming technique whereby a sheet of metal is formed directly with a hammer on a sinusoidal stake. A flat sheet is formed by stretching its edges and compressing the centre so that the surface develops two curves at right angles to each other.

Emery

Abrasive paper that is used to abrade surfaces. To achieve a fine finish on the metal surface, it is important to work through the grades of emery. As a guide the smaller the number the coarser the emery paper, for example 240 grit is quite coarse and 1200 is quite fine.

Flux

Usually in a paste form, it is a compound used to keep joins clean when soldering. The flux acts as a barrier to oxygen, preventing oxidising on the metal surface and allowing it to stay clean. Clean metal is important for soldering, it enables the solder to flow easily. If you over heat a piece, you can burn off the flux, in which case it will no longer be a protective barrier for your joins. It is best to stop and cool the piece, clean, re flux and begin soldering again.

Planishing

A finishing technique that involves fine hammering of the metal surface to smooth and refine it. The process of lightly hammering the surface also work hardens the material, which can give strength to a piece.

Piercing Saw

A small saw frame used to cut sheet metal, also known as a jewellers saw. It is a U shaped metal frame that comes in many different depths to allow cutting of small pieces right through to larger sheets. The saw blades are removable and are very much a consumable item and come in a range of different sizes. The sizing system of saw blades is a strange one, we put together a handy guide here.

PURITY MARK

Is an offical mark stamped into a piece to note the quality of the metal used. They are most often a number which represents the number of parts out of 1000 of pure metal in the piece. For example, 925 is the purity mark for sterling silver, which is traditionally 92.5% pure silver and 7.5% copper. 999 on the other hand is what’s known as fine silver, 99.9% pure silver. Something I recently learnt, the term Hallmark is reserved only for the purity stamps used by assaying offices which guarantees a certain purity or fineness of the metal, as determined by official metal (assay) testing. In Australia, we don’t have assaying offices, so jewellers and silversmiths mark their own pieces.

MAKERS MARK

A unique stamp used by jewellers and silversmiths (and many other craftspeople) to show that they are the maker of the work, much like a signature on a painting. Typically they are a representation of the makers initials or might also be a symbol. Makers’ marks are very useful in dating works and discovering who made a piece and its value. Makers marks are usually stamped along side the purity mark.

Raising

A metal forming technique used to create seamless hollow vessels through repetitive hammering, it also can be referred to as angle raising. Raising is primarily done using a specially shaped steel stake that the metal is hammered over in gradual stages.

Sinking

The first step when raising a hollow form. A flat sheet is gently hammered into a concave former (usually timber) to being to create a curved form.

Silversmith

Traditionally a craftsperson making hollow vessels in metal, however not restricted to working in only silver.

Soldering

A process in which two or more parts are joined by melting and flowing ‘filler’ metal (known as solder) into the join. Solder is an alloy, it melts at a lower temperature than the parent metal.

Work hardening

As metal is worked – that is, hammered, bent, shaped or formed – they begin to work harden. Not only does this present a challenge when continuing to form it, but will also become brittle and crack if overworked. In order to restore the metal’s workability, it needs to be annealed. Work hardening is an advantage in finished pieces, due to their increased strength.