In medieval Catalonia, or perhaps in the neighbouring province of Valencia, the manufacture of certain objects made of wood covered with thin sheets of brass bearing designs in relief seems to have formed a flourishing industry. The brass sheets employed, which covered practically the whole visible exterior surface and gave the appearance of articles of solid metal, were embossed by means of moulds into which the thin sheets were forced, so that their outer surfaces reproduced the designs of the mould. The process used is one which seems to have been in more or less general employment in medieval Europe; and many examples of it, frequently carried out in the precious metals, are to be found upon book-covers and caskets, and upon crosses, reliquaries, and other articles for ecclesiastical use. Long before the objects which I am about to describe were made, Rhenish, French, Italian, and Spanish craftsmen were using the process. Writing probably about the first half of the eleventh century, the monk Theophilus describes the process, especially in its application to silver and to copper gilt. He says that the stamps should be made of iron ‘thick as the size of a finger, wide as three or four fingers, in length one (foot)’, on which stamps, ‘in resemblance of seals,’, the designs are sculptured, not too deeply, ‘but moderately and carefully’. The metal to be used should be thinner than for ordinary relief-work. A sheet (in the case of silver), after having been cleansed with finely pulverized charcoal and polished with scraped chalk, is to be laid between the stamp (which rests face upward on an anvil) and a thick sheet of lead, and the lastmentioned is to be beaten strongly with a hammer. A sheet longer than a stamp can be moved so as to expose a fresh portion when one or more portions have been stamped.