A method for assembling a stone on to a mounting includes sinking the stone into an adhesive layer on a substrate and then positioning a setting sheet around the stone above the adhesive layer so as to form a peripheral free space between the setting sheet and the stone, at least at the level of the girdle and of areas of the crown and the pavilion adjacent to the girdle. Then, a metallic layer is deposited in the peripheral free space from the setting sheet, at least at the level of the girdle and of the areas of the crown and the pavilion adjacent to the girdle, such that the metallic layer and the setting sheet form the mounting.