Hallmark

[1] Hallmarks include information not only about the precious metal and fineness, but the country from which the item was tested and marked.

Responsibility marks are also required in the US if metal fineness is claimed, even though there is no official hallmarking scheme there.

A series or system of five marks has been found on Byzantine silver dating from this period, though their interpretation is still not completely resolved.

[4] From the Late Middle Ages, hallmarking was administered by local governments through authorized assayers.

The master craftsman was responsible for the quality of the work that left his atelier or workshop, regardless of who made the item.

Hence the responsibility mark is still known today in French as le poinçon de maître literally "the maker's punch".

In this period, fineness was more or less standardized in the major European nations (writ:[clarification needed] France and England) at 20 karats for gold and 12 to 13 lots[clarification needed] (75% to 81%) for silver, but the standards could only be partly enforced, owing to the lack of precise analytical tools and techniques.

Modern hallmarking in Europe appears first in France, with the Goldsmiths Statute of 1260[5] promulgated under Étienne Boileau, Provost of Paris, for King Louis IX.

In 1275, King Philip III prescribed, by royal decree, the mark for use on silver works, along with specific punches for each community's smiths.

This entity was headquartered in London at Goldsmiths' Hall, from whence the English term "hallmark" is derived.

In the modern world, in an attempt at standardizing the legislation on the inspection of precious metals and to facilitate international trade, in November 1972 a core group of European nations signed the Vienna Convention on the Control of the Fineness and the Hallmarking of Precious Metal Objects.

This mark is recognized in all the other contracting states, including: Austria, Cyprus, the Czech Republic, Denmark, Finland, Great Britain, Hungary, Ireland, Israel, Latvia, Lithuania, the Netherlands, Norway, Poland, Portugal, Sweden, Switzerland and Ukraine (see links below).

French mark head of horse for jewellery and watches from 18k gold made in the French provinces between 1838 and 1919 The Hallmarking Act 1973 (c. 43) made Britain a member of the Vienna Convention as well as introducing marking for platinum, a recognised metal under the convention.

Note that under this latest enactment, the date letter is no longer a compulsory part of the hallmark.

[20][8] Under the current law, on all gold, silver, platinum or palladium watches cases made in Switzerland or imported into Switzerland, there shall be affixed,[21] near the Maker's Responsibility Mark and his indication of purity, the official Hallmark, the head of a Saint Bernard dog.

In addition to the Swiss hallmark, all precious metal goods may be stamped with the Common Control Mark of the Vienna Convention.

This is significant since producers that exported precious metal goods to the Netherlands would have been required to register their marks.

The Netherlands' hallmarks are also recognized in other EU countries and thus can be sold in Austria, France, Ireland, Portugal, Spain and the United Kingdom without further testing.

Punches are made in different sizes, suitable for tiny pieces of jewelry to large silver platters.

A new method of marking using lasers is now available, which is especially valuable for delicate items and hollowware, which would be damaged or distorted by the punching process.

The age-old touchstone method is particularly suited to the testing of very valuable pieces, for which sampling by destructive means, such as scraping, cutting or drilling is unacceptable.

A rubbing of the item is made on a special stone, treated with acids and the resulting color compared to references.

Differences in precious metal content as small as 10 to 20 parts per thousand can often be established with confidence by the test.

As applied to gold bearing metallics, as in hallmark assaying, it is also known as cupellation and can have an accuracy of 1 part in 10,000.