What does M mean on jewelry?

On jewelry, what M means varies. The "M" hallmark usually signifies that the piece comes from a particular maker. However, several jewelry makers have used "M" hallmarks. Among them are Maui Divers, Mikimoto and Movado. For more information and assistance with identification, you can consult trusted online sources or an expert, such as a certified appraiser. Shop a wide range of jewelry on 1stDibs.