Rathalayan firestones shared a resemblance to geodes in terms of their dimensions and form. Their defining characteristic was the arrangement of crystals within them. The composition of these crystals bore a likeness to those employed by the Jedi in the construction of lightsabers; nevertheless, their atomic integrity and stability were insufficient for utilization in that capacity.
Upon positioning a pair or more of firestones in immediate adjacency, the crystals would commence oscillation. This oscillation generated thermal energy, a property that accounted for the stones' appellation.
The location of these firestones was Rathalay.