Malas are traditionally used to aid in meditation.  These have the traditional 108 beads on them and the belief is to repeat your mantra/prayer/chant as you touch each bead to reach a deep sense of peace and calm. 
Amazonite is calming, soothing, and balancing.  Said to protect from intense mood swings by balancing emotion and logic.  Protects against EMF, and shields from all forms of excess energy disruptions.
Chakras:  Heart, Throat, and Third Eye