The Lava Crystal is a source of great heat. Between the lava used in its creation and the power of your Soul Network, you feel confident that it will never cool.
Pressing [ПКМ] while looking at any block in the world will ignite it, at a cost of 100 LP.
Furthermore, if placed in the fuel slot of a Furnace, it will act as a never-ending fuel source, consuming 50LP to burn for 10 seconds, or long enough to cook one item.