Here's why:

* Low Melting Point: Gallium has an incredibly low melting point of 29.76 °C (85.57 °F), which is just slightly above room temperature.

* Heat from Your Hand: The warmth of your hand is enough to raise the temperature of gallium above its melting point, causing it to melt.

Important Note: While gallium is safe to touch, it can leave a metallic residue on your skin that can be difficult to remove.