Difference between revisions of "Non-ferrous Metalworking"
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Apart from iron and bronze, the Saxons and Vikings made use of other metals, mainly for jewellery. The most widely used of those used were silver, pewter and gold. Silver was a popular metal for jewellery such as brooches, rings, strap ends, buckles, mounts for drinking horns and, of course, for coinage. Silver jewellery was made in much the same way as bronze jewellery was, as the two metals have similar working properties. We do not know for certain how they polished their cast pieces, such as we do today on electric rotary mops. Although, Iron Oxide paste in wax was found in fairly large lumps at the Jorvik dig some years ago. This is by and large no different to 'Jeweller's Rouge' that is used today to polish silver and bronze. A popular way of finishing silver jewellery was to melt a black paste, called 'niello' (silver sulphide), into the recesses in the design to give a stark variance to the shiny silver. This was then polished, using ear wax as the final abrasive to contrast the silver. Iron objects were also inlaid with silver to decorate them, or sometimes were completely sheathed in a fine sheet of beaten silver.
The inlay is very easy to explain, but very tricky to do. Small lines or dots are incised or punched into the iron after the final smithing and finishing is done. Fine silver and \or copper wire is then drawn to the correct size, clipped to suit and placed into the incised lines on the ironwork. Then the wire is deftly beaten into the iron. The shape of the slot and the slight pinching effect of the iron as it is beaten grips the wire, holding it in position. Other silver jewellery was further enhanced by gilding (applying gold foil wash) over all or part of the surface. This was done by grinding up pure gold and mercury together, creating an amalgam. The paste was then applied to the appropriate areas of the work, and then heated in an oven, driving off the mercury as a toxic vapour. The gold was then bound to the surface of the work. Gold was also used to gild other metals to create the impression that the object was actually made of gold, or to add a contrasting colour. Several gilding techniques were in use, and evidence of mercury, as used in fire-gilding, has been excavated at York and Hedeby.
As well as silver ingots, either mined and cast into ingots or traded for, much of the raw material the silversmith used came in the form of 'hacksilver'. Hacksilver was basically scrap, ie.; unwanted as jewellery rather than substandard silver, and usually consisted of old and damaged silver objects, or coins often of a foreign origin etc..
The Vikings were particularly fond of silver arm and neck rings. These were produced either by plaiting and twisting silver wire or by hammering out a band from an ingot and punching it with decorative iron punches. Hacksilver often consists of sections of these arm and neck rings, which have arrived in the silver hoards as a form of payment, rather than using silver coins. Coins themselves were only ever made by moniers who were granted a special licence from the king. This was a highly regulated practice, with the dyes being updated and changed every few months to prevent forgeries being made. Breach of any of the laws regarding the striking of coin carried very heavy penalties. To make a coin the monier would punch a disc of silver of the correct weight and thickness and place it between two pieces of iron dyes with steel faces which had been engraved with the design of the usually the King on one side and a legend or cross on it's opposite face as required on the coin. He would then strike the top dye with a heavy hammer and the design would be stamped onto both sides of the silver blank. Coins, or pennies as they invariably were, were made from high grade silver of at least 925 parts per thousand purity or above. They were therefore a guarantee of quality, and even commanded a higher price than silver in the form of hacksilver, purely as it was assured as high quality silver.
Gold was virtually only ever used for jewellery which again was made in the same way as bronze jewellery, although the techniques of granulation and filigree work was often used to enhance gold jewellery. This often took the form of a thin gold sheet pressed via a bronze matrix and trimmed into shape. Thin drawn wires were then wound into various designs and applied to the surface of the gold sheet. A flux of pigs fat was already on the sheet to help temporally fix the wires in situ. These wires could also be impressed regularly, creating an unbroken beaded wire. When all the components were in place, the gold sheet was heated very carefully, fusing the gold wires to the surface of the sheet. This could be done again with fresh elements, however the first gold wire would slowly 'melt' into the background if too much heat was used. Particularly in the Saxon pagan period, gold jewellery was often inset with precious or semi-precious stones such as garnet. It wasn't done haphazardly, the garnet was cut into slices, and then shaped into regular or irregular polygons, and then arranged into patterns. The patterns were surrounded by gold fine gold walls creating separate cells for each garnet. Sometimes, each garnet was cut fine enough that an impressed gold foil with facets impressed on it, was placed underneath so that it would sparkle and reflect light back. On Bibles and other fine literary works, the wooden covers of these books were often not just covered with embossed leather, but polished precious and semi-precious stones set in gold collars. The greatest of these books seem as if a plate full of boiled sweets had been upset on them.
Much of the gold and silver was used in the production of ecclesiastical items such as altar-crosses, reliquaries, and portative altars; the church being the client who could afford such wonderful pieces of work. Gold and silver was also beaten and drawn out to be used to make thread for embroidery and braid weaving, often of an ecclesiastical in nature. Any that went to embellish the clothing of the upper classes, eventually arrived in the hands of the clergy as bequests later on. This clothing was then altered to become liturgical dress.
Pewter was used to make cheap jewellery and was cast in moulds made from antler, engraved Roman tiles and clay, although stamped pewter jewellery was also made. There are some examples from London which have been fashioned into crude 'flowers' of cast twisted wire, with small glass settings have been caught in their centres. There are also the odd find of pewter buckles, though these are small in size and not terribly robust. Lead was used to make window cames for holding stained glass in windows, and can be found particularly at cathedral sites. It was also used for roof flashings and weights for scales. These scale weights are often very accurate, and were decorated with small bronze and enamel disks on their tops.
Jewellery making was a specialist craft, and was frequently carried out at royal manors under royal patronage. However, the early mediaeval jeweller was not just a highly skilled craftsman, he was also a designer - often a true artist. Excavations on sites where jewellery making took place always produces a remarkable assortment of 'trial pieces'. These are animal bones, or occasionally stones, on which a wide variety of designs have been carved. The exact purpose of these are unknown, although some are clearly practice pieces on which the jeweller has tried out a new design, perhaps by apprentices who are training. Others have fully finished designs which could have been used for impressing wax masters, or casting lead versions that were then fettled to a fine finish, encased in clay and fired. This would seal the clay and void the lead in the same fashion as 'cire perdu' or lost wax for one-off casts. The lead model could be handled more roughly and would take a very crisp image. These bone trial pieces could have been a 'pattern book/catalogue' to show prospective customers.
Straight Tin was sometimes used to coat iron objects (such as helmets) to make them shine and to prevent them rusting. It was also employed to coat the insides of iron cauldrons for the same reason, and it had the beneficial effect of being a fairly sterile surface on which to cook and clean the pot.
Another specialist type of metalwork was bell-casting. St Dunstan is known to have made bells in his youth, but traces of bell-casting are rare. A datable pit was found at Winchester and was presumably used for the casting of the bells of the Old Minster between 971 and 980AD. In the harbour site at Hedeby in Northern Germany, a bell and it's suspension mount of wood were found. The bell is not that modest at around 18 inches high and 12 inches in circumference. The Bayeux Tapestry shows small boys or attendants with hand bells at Edward the Confessors funeral cortege.
Original article by Roland Williamson 2002