An interesting state of water is water at and above its critical point. The critical point is where the boundary between the gaseous and liquid states gets fuzzy. This occurs at 647 K (374 °C; 705 °F) and 22.064 MPa (3200 PSIA or 218 atm) for water. Water becomes a dense fluid that is neither gas or liquid, but is sort of both at the same time. It acts like a gas, but because of pressure it is as dense as a liquid. Supercritical water becomes a very aggressive solvent for minerals, rocks and organics.