Sharnax was a planet originally controlled by the Drashani Empire. It was mostly covered in marshes and had a slightly acidic atmosphere.
The House of Sorsha had mining operations on the planet.
During the civil war between the Houses of Gadarel and Sorsha, Sharnax was overrun by Igris. A decade later, Princess Aliona crashed on Sharnax. A rescue team was sent out, but it also crashed on Sharnax. (The Burning Prince)