Ruisha is a rare and valuable gemstone native to Kanbal. They are blue in color and are found in the deepest depths of the mountains. The luminous stone actually glows in the dark and is very precious due to its rarity.
Various myths exist in Kanbal regarding how ruisha is formed. The gem is known as the "heart stone" by herders in Kanbal, as the hyohlu - the "Guardians of Darkness" in the sacred Mountain Deep of Kanbal - are said to take the hopes and sorrows of lives of the King's Spears who enter the mountains. The feelings are transformed into a blue light, allowing the hyohlu to return to the earth to die a true death; the ruisha are believed to the crystallized thoughts and wishes of the men who died in the caves.