Here's why:
* Olivine: A silicate mineral with a high density, typically found in the Earth's mantle.
* Peridotite: An igneous rock composed primarily of olivine, along with other minerals like pyroxene.
Peridotite is the main constituent of the Earth's upper mantle. Because of its high density and olivine content, it is heavier than most other rocks found on the Earth's surface.
