Mabe' pearls appear as a large half pearl but in fact they form as a dome on the inside lid of an oyster and are cut away from the shell itself. Generally they are used for larger earrings and backed with a gold setting and have an advantage of a wide diameter but low depth. Although a variety of shapes exist, most mabe' pearls are round. They are particularly suitable when surrounded by a line of small diamonds, with the pearl at the centre of the cluster. In the 19th and early 20th centuries they were called "blister pearls" which had limited modern marketing appeal! The name Mabe' was later adopted, a name derived from the Japanese word meaning "half".