This locket is part of the Apothacary  collection of magical potions and ingredients. As an ingredient Bleeding Heart was said to be a 'cure for grief' as stamped inside (remedy for happiness).
It's approx 4cm x 2.5cm x 0.8 cm. The oval stone is a rainbow moonstone and the stopper is a 5mm rose cut garnet. 
The chain can be worn at 2 lengths 20 and 22 inches. 
Sent special delivery.