A tanray heart crystal.

Tanray heart crystals, also known as lava lizard hearts, were a type of crystal found on the planet of Mustafar. Formed under the intense heat and pressure of the lava world, the end product resembled the heart of the tanray, hence its name. Sometime following the Battle of Yavin in 0 BBY, surveyor Jo Kelsev gave a spacer one of these crystals as a reward for activating all the markers he had placed in regions across Mustafar. This particular tanray heart crystal was mounted on a black colored base, so that it could be displayed as a trophy.