On Divers Arts, The Treatise of Theophilus, John G. Hawthorne and Cyril Stanley Smith, translators. University of Chicago Press 1963, 1976. Also available in a Dover edition; I do not know if the translation is the same.
This is a medieval craftsman's manual, probably from the 12th century. It contains one section on the art of the painter, one on the art of the worker in glass, and one on the art of the metalworker. The third section is much the longest and most detailed, and it seems likely that the author was himself a metalworker. It includes instructions on setting up a shop, making tools, and using them for a series of projects.
The Treatises of Benvenuto Cellini on Goldsmithing and Sculpture, C.R. Ashbee, translator. Dover 1967.
Cellini was a sixteenth century Italian craftsman, author of both this book and a famous autobiography. The treatise on goldsmithing contains a great deal of technical information on period techniques, mixed with anecdotes designed to demonstrate the superlative wisdom and skill of the author.
Metalwork and Enamelling, by Herbert Maryon. Dover 1971.
Maryon worked for many years at the British Museum; he was responsible, among other things, for the reconstruction of the Sutton Hoo treasure. His book is a detailed and carefully written manual. It should be particularly useful to SCA jewelers for two reasons. First, he describes many period techniques, not as matters of merely antiquarian interest but as practical ways of making jewelry. Second, he assumes that the reader will have to do a good deal of improvisation, including making much of his own equipment. In one of his chapters on soldering, for example, he not only explains how to make a jeweler's furnace but even tells the reader how to make his own charcoal.
These three books are the best sources I know of for learning how to make period jewelry.
Most of the books on historical jewelry that you will come across are coffee table books, designed more for beauty than information. While they contain pictures of some magnificent pieces, they tend to be mostly the same pieces in every book. It is worth getting one or two such books (preferably second hand, or remaindered, or on discount from Publishers Central, since they are usually expensive otherwise), but the additional information you get from additional books decreases rapidly.
Three exceptions to this rule are:
Jewellery of the Ancient World, by Jack Ogden, Rizzoli, 1982.
Jewellery Through 7000 Years, British Museum Publications Limited, 1976.
Jewelry Ancient to Modern, Anne Garside Ed., Viking Press, 1979.
The first of these contains the most careful and scholarly discussion of what stones and techniques were used when that I have ever seen. Unfortunately, since Ogden's subject is jewellery in classical antiquity, he says relatively little about the Middle Ages and Renaissance. The second book describes the collection of the British Museum, and the third the collection of the Walters Gallery in Baltimore. Each contains pictures and descriptions of a large number of pieces. They provide the closest approximation available (short of going to museums) to primary sources for jewelry history.
If a really adequate secondary source on jewelry history has been written, I have not seen it. The closest thing I know of is not a jewelry book at all but a costume manual: Costume and Fashion by Herbert Norris. Along with his description of the clothing of each period he has a fairly detailed discussion of the jewelry. Since he is writing about English costume, the information is useful for western European personae, less useful for others.
Three other books I would recommend are:
Anglo-Saxon Jewellery, by Ronald Jessup. Shire Publications, 1974.
European Enamels, by Isa Belli Barsali, translated by Rudolf Rudorff. Hamlyn, 1969.
Medieval Goldsmith's Work, by Isa Belli Barsali, translated by Margaret Crosland. Hamlyn, 1969.
These are relatively small books, each specializing in a particular area. There are probably other, similar, books that I have not come across. One can also sometimes get information on jewelry from books on a specific culture, such as The Viking or Treasures of Ireland.
[Originally printed in A Book of Bibliographies for the Arts and Sciences in the Current Middle Ages, Airmid Godwin, ed.]
Webbed by Gregory Blount of Isenfir