Dioptase is an emerald green Copper Sulphate with a hardness of 5 on the Moh's scale. As a member of the Trigonal crystal Family it forms beautiful Rhombohedral crystals as in the  pic.

Most Dioptase is found in Kazakhstan.

That rich emerald green of Dioptase opens and inspires the heart. It's a powerful stone to awaken love and compassion and to heal emotional distress. The beautiful green of Dioptase makes it a healing heart stone on many levels. Emotionally spiritually and physically it bathes the Heart in love and Healing.