The art of the Yemenite silversmiths has a long history. It usually runs in family's veins for generations - from father to son.Filigree (formerly written filigrann or filigrene) is a delicate kind of jewellery metalwork made with twisted threads usually of gold and silver or stitching of the same curving motifs. It often suggests lace, and in recent centuries remains popular in Indian and other Asian metalwork, and French from 1660 to the late 19th century. It should not be confused with ajoure jewellery work; while both have many open areas, filigree involves threads being soldered together to form an object and ajoure involves holes being punched, drilled, or cut through an existing piece of metal.The word, often thought derived from the Latin filum, thread, and granum, grain, is not found in Du Cange, and is indeed of modern origin. According to Prof. Skeat it derives from the Spanish filigrana, from "filar", to spin, and grano, the grain or principal fibre of the material. By extension, it may be used in a number of contexts to describe anything considered delicate, intricate and elaborate.