Hematite

Hematite is a stone for the mind. It developes one's mental dexteriy, enhances memory , critical thinking, and technical knowledge.
It provides for a claming atmosphere, and helps one to realise their own self-imposed constraints.
It facilities the balancing of yin-yang energies, and its magnetic property balances the meridians of the body, and provides a stable equilibrium between one's ethereal and physical nervous system