Manufacturing Masterclass

One of the many reasons to collect silver is to appreciate the art of the silversmith and I thought if I described the method in detail from start to finish on one particular item it may give an interesting insight. The item I have chosen is the sterling silver James style goblet which will grace any type of home from a classic ‘olde worlde’ to a more contemporary one. It is a joy to use, being a piece of handcrafted work of lasting value in contrast to some of todays landfill production. It is a treasure to pass on to future generations and will make a great talking point at the dinner table.

I had been skeptical of mixing old with new until I saw an exhibition by contemporary silversmith Stuart Devlin where his contemporary range was displayed on antique furniture in a Bond Street retailer some years ago.

The method of production is an interesting one, created by the Master Silversmith (an eminent member of society in days gone by) from 4 main components of sterling silver. The bowl, then a reinforcing plate, a cast stem and finally the base. Since the Birmingham silversmith Matthew Bolton invented the rolling mill silversmiths have had a relatively easy life. Prior to this the silversmith first had to alloy his sterling silver by melting and mixing the correct ratio of silver and copper(925% silver and .75% copper) pour it into an ingot mould, beat it with large heavy hammers on an iron block, with frequent annealing (making it red hot) in between hammering sessions to re soften the expanding block until it was eventually thin enough sheet to make the final product. This must have been a days work in itself!

Todays silversmith buys readymade sheet from the shelf from a bullion dealer. He then cuts the several silver discs for all the components(except the stem) and proceeds to spin the bowl part of the goblet. This has to be done in several stages removing the part from the chuck on the spinning lathe and annealing. This is done to soften the part which becomes work hardened during spinning  becoming difficult to handle and possible cracking. Upon completion of the bowl, part 2 a small thick disc about the size of a 1p coin is domed and soldered to the underside of the bowl, this is to strengthen the area where the stem will attach and stop damage occurring.

The next component is the cast stem. A process usually subcontracted to the specialist caster. Until recent times this work would have been done in a (2 halves) sandbox from a master pattern, 1 by 1 in each box. Today’s preferred method is the ‘lost wax’ method. From a master pattern a vulvanised rubber mould is made and a wax produced. These waxes are then inverted in a plaster cast, heated, and the wax melted out leaving the impression of the waxes inside. Molten silver is then centrifuged into the plaster. Once cooled the plaster is then cracked open and the cast components removed.

In this case the cast goblet stem is soldered to the sub assembly components 1 and 2. Last is the silversmithing process in the base. This is again the spinning process discussed above. The base is then soldered to sub assembly 1-2-3 to make the finished but unpolished and unhallmarked goblet. At this stage it has a flat milky coloured surface which is the pure silver at the surface of the metal (the copper at the surface having been removed by  immersion in sulphuric acid which removes the fluxes used in the soldering process.

Next in the process is a visit to the London Assay office housed in Goldsmiths Hall London where each of the 4 components are tested (which its self is an ancient and fascinating technique) A small sample is removed by scraping or ‘scratching’ as it was called historically. The commonly used term in English ‘up to scratch’ is in fact a precious metal testing term. If the results are positive the ‘hallmarks’ are punched into the surface in a position of the silversmiths choosing. The article is supported on an iron stake to enable punching.

Upon returning to the silversmiths workshop the small dent (caused by the punching of the hallmark are removed. The piece is finally polished using 4 grades of abrasive, terminating in jeweler quality rouge which imparts the final luster.

And in the case of a drinking goblet, the inside of the bowl is gold plated which eliminates any chance of a slight coppery taste which might be experienced without this guilding.