Gallium has a melting point of 29.76°C (85.57°F), which is just below normal human body temperature. When held in a warm hand, gallium will melt from solid to liquid. Bauxite is an aluminum ore (ore, not metal), coal is not a metal, and magnesium melts at 650°C, far too hot for hand melting. The question claims 'only' but several alloys also melt at hand temperature.