A jewelry maker's mark is a personal trademark of an individual jeweler. Often, a maker's mark is registered with the authorities in the local jurisdiction, so that the pieces may be tracked to him or her.
A maker's mark is one of the methods used to identify a piece of jewelry and its origin. It carries an identifying mark of the jeweler who is accountable for the amount of precious metal in the jewelry. A number of American jewelers, including Aletto Bros, the Cellini Shop and Julius Cohen have recognizable maker's marks. While it is often helpful to appraisers and researchers, it is not as precise in certifying this information as a hallmark.
A hallmark differs from a maker's mark in that it is issued by the assay office of the local jurisdiction and serves as a foolproof way to identify jewelry and who made it. The United States does not have an official system for hallmarking; therefore, jewelry made in the U.S. is not officially hallmarked. American jewelry makers such as Tiffany and Co. have to send their products to Europe to be hallmarked so that they may legally be sold on the European market.The Hallmarking Convention, formed in 1976, oversees this process. There are 19 member countries, including the United Kingdom, Switzerland and Austria.