No, the Earth’s crust is not denser than the mantle. In fact, the mantle is significantly denser than the crust.
The Earth’s crust is composed mainly of lighter rocks such as granite and basalt, which have a lower density. Granite, common in continental crust, has an average density of about 2.7 g/cm³, while basalt, predominant in oceanic crust, is denser at around 3.0 g/cm³.
On the other hand, the mantle is made up of denser materials, primarily silicate minerals rich in iron and magnesium. The average density of the Earth’s mantle is approximately 3.3 to 5.6 g/cm³, depending on the depth and composition of the mantle materials.
Therefore, even though individual sections of the crust may vary in density, the overall average density of the mantle outstrips that of the crust significantly, illustrating how the deeper layers of the Earth contribute to the structure and dynamics of our planet.