Diamond lightning and bell (Vajra, Gantha-Rdorje, Drilbu) in their case, Tibet, 19th - 20th centuryBrass and copper alloy. The outside of the case is made of black lacquered canvas on a wooden core, the inside is covered with a textile printed with a flower motif. Height of the bell : 19 cm ; length of the vajra : 13 cm ; total height with case : 20 cmThe legend says that to make a bell it is essential to use an alloy made of the seven essential metals : silver, copper, tin, iron, mercury, gold and lead .