Malachite

Malachite is called the "stone of transformation" and is used for deep energy cleaning. 

An important protection stone.  Malachite absorbs negative energies and pollutants, picking them up from the atmosphere and from the body. 
Malachite amplifies energies of all kinds, both positive and negative. Said by some to be one of the most important healing stones, Malachite helps the user acknowledge, draw out, and discharge negative energy, including old emotional patterns, past traumas, and suppressed feelings.

Chakra- Heart