Sum is the sigil of Peace. To study Sum is to seek inner peace and to know the undying nature of the Realm's energy. The reflecting pool of creation, Sum’s sphere of influence, covers meanings from harmony to stagnation. To study Sum is to know the undying nature of the Realm's energy and the rebirth of all.
Sum is composed of two spheres, one inside the other, attached by two bars. This represents the peace within. Some claim that the symbol is representative of the child in the womb, but there is nothing to substantiate this.
As a Warrior Stone, Sum tends to have sigils on top, underneath it, and/or inside it. As a Booster Stone, it does the same action, except onto another sigil.