Mellerio dits Meller is a French jewelry house of Italian origins, founded in 1613, and still active today. It is the oldest family business in Europe. It gives its name to the Mellerio cut, a 57-facet jewel cut, shaped as an oval within an ellipse. Today Mellerio has its headquarter in rue de la Paix, Paris, with branches in Luxembourg and Japan. Mellerio is a member of the Comité Colbert and also of Les Hénokiens, an international club made up of family companies over 200 years old. In 1777 Jean-Baptiste Mellerio (1765-1850) started trading in Versailles attracting the patronage of Queen Marie Antoinette.
The Mellerio Shell tiara was given to Infanta Isabella of Spain as a wedding present from her mother Queen Isabella II in 1868. Mellerio had made The tiara for the 1867 Paris Exhibition. It is made of diamonds in the shape of shells decorated with pearls.