In 2002, the American Gem Trade Association (AGTA) selected tanzanite as a December birthstone, adding it to a list of birthstones unchanged since 1912. Interestingly, despite its official status, tanzanite is being increasingly regarded by people around the world as the birthstone, irrespective of the month, as a celebration of new life and new beginnings.  
This growing practice has its roots is Masai custom, which upholds the color blue as sacred and spiritual. Only women blessed with fertility have the honour of wearing blue beads and fabric. Since the discovery of tanzanite, a new tradition has evolved whereby Masai chiefs give tanzanite to their wives on the birth of a baby to bestow upon the child a healthy, positive and prosperous life.