Here's why:
* Mantle: The layer of the Earth between the crust and the core. It's primarily composed of solid rock, but it's also very hot.
* Magma: Molten rock found beneath the Earth's surface. It forms when rocks in the mantle melt due to increased temperature and pressure.
* Lava: When magma reaches the Earth's surface, it's called lava.
So, while the mantle itself is mostly solid, the melted portions are referred to as magma.
