As was determined in the 20th century, Earth's mantle is much richer in heavy minerals than the crust we walk on. However, getting those riches to the surface is extremely problematic: not only it requires drilling for many kilometres (as the crust can be even 50 km thick), but also withstanding enormous pressures and temperature that occur at such depths. Those problems were to be overcome though: recent advances in Mantle Engineering allowed Indian company called Brahmos Inc. to drill their first Thermal Boreholes in deepest parts of the Indian Ocean, where the crust was no thicker than 5 km. A Thermal Borehole used heavily modified and expanded mining forcefields, not only reaching deeper than anyone before, but also achieving marketable results. This new form of mining was very expensive, but it allowed relative independance from space excavation: a feature much sought-after.