The Earth’s mantle, based on observations of density and shock waves travelling through it appears to be a thick, hot toffee-like, convecting layer of materials ranging from about 2000 degrees C under the Earth’s crust to almost 4000 degrees C where it ends at the outer core. read more
The Earth’s mantle is a layer of the Earth between the core and the crust, made of plastic rock. It flows mostly slowly. Some of it is erupted out of the Earth. read more
I actually think the mantle is part of the Earth so there's basically no function to it. read more