Final answer:
The mantle is made up of solid rock, while the crust is largely composed of oceanic basalt and continental granite. The mantle is about 2,900 kilometers thick and is composed of relatively solid rock.
Step-by-step explanation:
The mantle is made up of solid rock. Scientists have determined this based on evidence from seismic waves, heat flow, and meteorites. The crust, on the other hand, is largely composed of oceanic basalt and continental granite, both of which are igneous rocks that have cooled from a molten state.
More specifically, the oceanic crust is primarily made up of volcanic rocks called basalt, while the continental crust is predominantly composed of a different volcanic class of silicates called granite.
The mantle, which is about 2,900 kilometers thick, is composed of relatively solid rock. Samples of upper mantle material can be occasionally ejected from volcanoes, allowing for detailed analysis of its chemistry.