Prasiolite aka Green Amethyst.
The purple Amethyst crystals may be naturally transformed into Green Amethyst by the heat within the earth. These days a similar process is done artificially, by heating the stone in kilns.
A strengthening of your relationship with the Divine mind is a natural consequence of its use. The special gift of Prasiolite is to bring your focus to a truly heart based perspective.
Keeping Prasiolite near your heart protects and strengthens your aura. As well as your upper chakras.