1 to 6 years. The life of the magnetic clasp of the necklace is determined by how many years it is worn. It can be used for 5 to 6 years in the case of frequent wading and strenuous exercise, with a life of 1 to 2 years and frequent maintenance. Necklace is a chain jewelry made of gold, silver and jewelry. It is one of the ornaments of human body and the earliest jewelry.