Identifying Japanese ceramics and porcelain through the signatures and marks on them can be difficult, since many makers used combinations of similar markings. These did not so much indicate maker, date and location, as they symbolized messages of good fortune, such as love, happiness and luck. The Noritake company, for example, has used more than 400 different marks in its history, and like other companies, has subcontracted its marks out to other mass producers. However, the style of the piece, its decoration and glazes also give experts valuable indicators as to the origin of Japanese ware.
Research the history of Japanese signatures and marks and familiarize yourself with some basic knowledge to help you make an informed decision on the piece you are looking at.
Purchase a pictorial guide to marks such as Chad Lage's "Pictorial Guide to Pottery and Porcelain Marks," or "Miller's Pottery & Porcelain Marks: Including a Comprehensive Guide to Artists, Makers, Factories and Forms."
Examine the piece closely for all signatures and marks. As well as looking on the bottom of the piece, check for markings inside the piece and within the decoration itself. Twentieth-century mass market pieces commonly feature English words such as "Noritake" and "Nippon" which mean they are from Japan. The word "Nippon" was used until 1921, when the U.S. government insisted that imports for the U.S. market be marked "Japan" instead. The phrases "Occupied Japan" and "Made in Occupied Japan" mean that the pieces were made between 1945 and 1952.
Compare the signature and marking with the many examples in your pictorial guide, or at the website www.gotheborg.com. This is the best way for an amateur to home in on the origin of a piece. You will soon become familiar with some simple marks, such as a mark within a fan which means it is Izumi ware; the image of Mount Fuji and a stream, which means it is Fukagawa ware; and rising sun motifs which date pieces to the late 1940s.
Take a photo of the signature and markings and consult more than one expert, if you want to definitively identify a piece, prior to purchase.
Before spending a significant amount of money on a piece of Japanese ware, it is a good idea to have the piece authenticated by at least one expert, who has many years' experience in Japanese ceramics and porcelain.
An auction house will not attribute a piece it is selling to a specific maker, unless it is absolutely sure it is authentic.