To check whether or not a Nippon china tea set is genuine, check the stamp on the back of each piece. Examine the level of workmanship in painted details, and any gold details. Each piece's glazing, and any signs of wear, can also provide clues to the tea set's authenticity. An antique Nippon porcelain dealer should be able to vouch for his products, and customers making large purchases should request a written guarantee of authenticity.
Producers of modern Nippon china reproductions often use slightly altered versions of the original backstamps. The backstamp is placed on the bottom of each piece of china. The backstamp on reproduction Nippon china often includes an hourglass in a wreath, a rising sun mark or a maple leaf mark. The size of the maple leaf and the style of writing in these backstamps can help to show whether or not a piece is authentic.
Producers of reproduction Nippon china have used an exact copy of the Nippon "M in wreath" stamp to mark their china. A U.S. Customs ruling states that the fake mark cannot be imported into the United States, however pieces bearing the mark that were imported prior to the ruling are still in circulation.
Genuine Nippon china exhibits fine craftsmanship, with multiple colors used to give depth to painted flowers and leaves. Antique Nippon china maintains its finish after years of use, while modern reproductions may have a poor quality finish or look suspiciously new.