Double fish are used as a symbol in some Asian cultures to bring awesome abundance, happiness & luck! This is a very brief description, and if you research this further you will find a wealth of information about the beliefs of the double fish symbol.
Measurements: Size: about 25.5mm long, 22.5mm wide, 9mm thick, with a 1.5mm threading hole
Quantity per pack: 2
Today's cinnabar is most probably made from resin - sometimes still hand carved, and totally safe to wear. Centuries ago, people became very ill from making/wearing cinnabar due to it's mercury content!