POTTERY MARKS

 The marks stamped or printed on the underside of a piece of pottery can be a frap for the unwary but will usually yield some useful information about where and when it was made.

 The practice of identifying the maker of a pot by marking the base dates back to at least Roman times, but the first modern factory mark appeared in 16th century Europe. The crossed swords painted on Meissen porcelain from 1723 helped to spread the practice. In France, porcelain makers were required by law to register a mark from 1766 on, but in other countries marks had no official status.

 As a result, while the top makers usually, but not always, identified their pieces, others either left their wares unmarked, in the hope that they would be mistaken for something better, or shamelessly put on copies, or near relations, of famous marks.

 The crossed swords of Meissen, interlaced Ls of Sevres and crescent of Worcester were all widely copied in the 18th century and beyond. The firm of Samson of Paris reproduced a great deal of classic 18th-century porcelain in the second half of the 19th century, complete with versions of the appropriate marks. The gold anchor of later Chelsea porcelain is more often seen on Samson reproductions than on originals.

 From the early 19th century on, factory marks were increasingly applied to all forms of pottery. There was a practical reason for this. The century saw a shift away from fairs and travelling peddlers towards retail stores as a means of selling; retailers used the information in the factory mark to re-order popular items. As a result, printed marks of the period, particularly on useful wares, often contain the name of the pattern and shape as well as that of the maker.

MAKING A MARK

 There are several ways of applying a mark. They can be incised, or cut freehand into the soft clay before firing; impressed into the soft clay with a special stamp or seal; painted at the time of decoration (this type includes stencilled marks); or printed. More unusually, you will find a mark raised in relief; in almost every case, the piece will have been moulded and the mark cut into the mould. There are a few exceptions, where a piece of shaped clay was added to the base before firing, but such marks were much too easy to fake; the rare raised anchor mark of Chelsea porcelain appears more often on fakes than the genuine article.

 Incised and painted marks are characteristic of small scale production. Incised marks are usually those of a modeller, so are usually seen on one-off pieces. They can be recognized by their free-hand look and sometimes sharp, but always raised edges. Impressed marks can be recognized by their regularity and smooth outlines.

WORKMEN'S MARKS

 Painted marks are usually applied by a decorator. They appear on studio pottery and also on factory-made pieces. On the latter they usually take the form of workmen's or tally marks, initials or cyphers that were put on by decorators to make sure they would be paid for every piece they worked on. These were often seen on early Worcester porcelain, for example. Marks in gilt are almost always tally marks put on by gilders.

 Marks could be painted or printed over or under the glaze. Those painted or printed in underglaze blue are usually genuine, at least in the sense that they were put there when the piece was made. Marks over the glaze in enamel colours are easily faked; always treat them with caution.

 Dates in marks can often be misleading. Some factories date marked their pieces as a matter of course, but usually with some sort of code. Any four-figure date that appears, particularly on a printed mark, will almost certainly be the year the company was founded.

 One base mark that can be particularly useful in dating a piece is the Registered Design or Patent Office mark, introduced in 1843 when manufacturers were permitted to 'patent' new shapes and patterns for a three-year period. Between 1842 and 1883 the mark took the form of a diamond containing code letters and numbers giving the day the design was registered and its place in that day's list. Impressed or moulded diamond marks usually refer to the shape of the piece; printed ones to its decoration.

 The day and list number are in figures, while the year and month are in code letters. The year letter was at the top of the diamond for the first 26 years, and was switched to the right corner in 1868, when the day of the month appeared at the top. In both runs, the sequence of letters was X, H, C, A, I, F, U, S, V, P, D, Y, J, E, L, K, B, M, Z, R, 0, G, N, W, Q, T.

 The coded date is the earliest the piece could have been made. It could, of course, have been made at any time after, but in practice, Registered Design marks were seldom added after the three-year period.

 Registered Design marks are found on other materials than pottery. The circle on top of the diamond contains Roman numerals that identify the type of object and are known as class numbers. All ceramic pieces are IV.

 In 1884, a simplified system was introduced which still applies today. Each new design was given a number in a single sequence, starting at 1. This number can give you the year of registration. As a rough guide, 100,000 was reached in 1888, 250,000 in 1895 and 500,000 in 1907. After this, things slowed down somewhat, and a million was not reached until 1981.