Identifying a paperweight as antique is difficult enough---identifying the manufacturer of an antique paperweight presents its own challenges. Paperweights normally do not have signatures or carry any type of markings to help locate manufacturers. However, many manufacturers had trademark techniques or patterns that make certain paperweights identifiable. Education is vital to being able to identify paperweight manufacturers. Reading expert guides, learning about the glassmaking process and viewing examples of antique paperweights will help train you to recognise authentic antique paperweights by manufacturer.
Read authoritative guides and encyclopedias of antique paperweights for history, manufacturing details and colour photographs. Recommendations by the Paperweight Collectors Association, Inc. include "Encyclopedia of Glass Paperweights" by Paul Hollister, three separate technique-focused "Identifying Antique Paperweights" guides by George Kulles, "Collectors' Paperweights Price Guide and Catalog" by Lawrence H. Selman and "Paperweights of the 19th & 20th Centuries: A Collector's Guide" by Anne Metcalfe. The Association's website at Paperweight.org offers a comprehensive book list in PDF format.
Learn glassmaking terminology and styles of antique paperweights. You should be able to identify canes, lampwork, sulphides and millefiori visually as well as knowing the definitions. Canes are glass rods created when molten glass is stretched from both ends. Lampwork involves melting glass with a flame and forming it into shapes. A sulphide is a cameo-style paperweight depicting a person or thing, such as a building, in bas-relief. Millefiori, Italian for "thousand flowers," is a design in which a glassmaker fuses thin slices of patterned canes into a dense mosaic.
Review the history of antique paperweights and learn the top manufacturers by country. This gives you a timeline for knowing when certain styles of paperweights were being manufactured and when the makers were doing their best work. The classic age of antique paperweights was 1845 to 1860, when French manufacturers Baccarat, Clichy, St. Louis and Pantin made the most renowned and artistic paperweights. Bacchus was a well-known English manufacturer. In America, the Boston & Sandwich Glass Company and the New England Glass Company manufactured paperweights from 1851 into the 1880s. C. Dorflinger & Sons, Mount Washington Glass Company, Whitall Tatum Co., Gillinder and Tiffany also made paperweights through the early 20th century that are prized by collectors.
Study the characteristics of various manufacturers' paperweights, including the kinds of canes used, signature techniques for shaping and encasing designs, and trademark patterns. For instance, Baccarat's millefiori used cane cross-sections that showed stars, shamrocks and silhouettes such as dogs and doves. Clichy's trademark cane rose appeared in 30 per cent of its paperweights. A trademark design of St. Louis was the "crown," which alternated glass filigree and ribbon twists. Pantin presented striking examples of lampwork, including realistic glass creatures such as salamanders.
In America, Sandwich placed lampwork flowers in delicate baskets within its paperweights. Whitall Tatum made the distinctive "Millville" rose paperweights around 1905. New England Glass Company was known for flower and fruit paperweights, with fruit pieces sometimes blown to scale.
View examples of antique paperweights in person, if possible. Some antique shows may include dealers who can discuss paperweights, even letting you hold and examine them. Regional museums and galleries may also display antique paperweights.
If you can't view antique paperweights in person, take advantage of colour photographs in reference books and online. They are no substitute for viewing the real thing, but photos might help you learn the "look" of certain manufacturers' paperweights. Examine modern paperweights as well. Learning the difference between antique and contemporary versions will help you in the process of identifying paperweights.
Don't expect to become an expert overnight, and don't assume that specific characteristics of paperweights are exclusive to certain manufacturers. Building your knowledge helps, but even experienced collectors can be fooled.