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5. ELKINGTONS' & THE ASSAY OFFICE


Explore the Birmingham Jewellery Quarter

 

THE EXTRA

This page reproduces in printable format the information contained in the right hand column of the walk page.

PLATING TECHNIQUES

 Sheffield plate was introduced in the 1740s and remained the method of producing silver plate until superseded by electroplating. The process involved taking a thin sheet of silver which was laid on an ingot of copper and hammered to ensure that the two metals were in contact over the whole of their surface area. The copper and silver were then bound round with copper wire and heated in a furnace until they fused together. The ingot was then rolled to produce a bimetallic sheet from which plated goods were fashioned.

Gold plate made by the analogous process was known as rolled gold.

Gilding was another early method of applying a gold finish. Ground gold was mixed with mercury to form a paste which was painted onto the article to be gilded. Heat was then applied to vaporise the mercury. A beautiful finish could be obtained, but the process was  detrimental to the gilder's health.

Electroplating can be used to plate goods with a wide variety of metals, the process being essentially the same in every case. In silver plating, the object to be plated ( a vase, let us say) is first fashioned in nickel silver ( a silvery-looking alloy of nickel). The vase is then immersed in a bath containing a solution of a salt of silver, and connected to the negative terminal of a battery, the positive terminal of which is connected to a rod of silver which is also immersed in the bath. When the silver salt is dissolved  it ionises and positively charged ions of silver are attracted to the negatively charged vase, which acquires a coating of silver. At the same time ions flow from the silver rod into the solution, replacing those that have been plated out. Electroplating has now replaced all of the earlier processes, rolled gold apart.

COLLODION

 Collodion is a solution of gun cotton in a mixture of ether and alcohol. It used to be used in place of plasters as a waterproof covering for wounds. Colloquially known as 'artificial skin', it came in a bottle with a brush in the cap and, when painted onto a wound, formed a plastic-like skin. 

HALLMARKING

Hallmarking is the world's oldest form of consumer protection, having been introduced in England in 1300 under an Act of Edward I. It involves stamping jewellery which has been assayed (tested) with a distinctive mark in order to certify the precious metal content. (Since pure gold, silver and platinum are too soft to be used in jewellery, in practice all jewellery is made from alloys of varying degrees of purity.) Articles found to be substandard are broken up and the materials returned to the maker.

The Assay Office is supervised by a Board of Guardians, only a proportion of whose members may be drawn from the jewellery trade.

EMPLOYMENT & OUTPUT

There are no accurate figures for the numbers employed in the jewellery trade. However, the general trend is clear. From around 6,000 in the mid 1800s it rose erratically, with many ups and downs on the way, to a peak variously estimated between 35,000 and 70,000 in 1913, falling sharply in the depression. Both world wars hit the trade badly, as did the punitive rates of tax in force after World War 2. In 1947 employment was estimated at 19,500. It is now said to be around one-third of that level. There are several factors behind this: increased productivity resulting from the introduction of modern manufacturing methods, the movement of some larger firms away from the Jewellery Quarter, and higher import penetration. 

The Assay offices figures for gold and silver assayed in Birmingham tell a similar story. To take just a few years at random, in 1774 17,000 ounces were assayed; 1837 111,000; 1890 1,471,000; 1913 4,639,000; 1932 2,389,000; 1953 569,000; 1972 1,423,000.  

 

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2001 Bob Miles