The sons in the next generation inherited vast fortunes and were renowned for their extravagance but also for their charity. The younger son, Nikita Akinfievich Demidoff (1724–1789) owned mines and steelworks in the Urals and Siberia as well as vast tracts of land. He was the first in the family to become a patron of the arts and sciences. A well–travelled man, he corresponded with Diderot and Voltaire.
Nikita’s eldest son Akinfiy Nikitich Demidoff (1678–1745) expanded the family empire with the addition of eight munitions factories and steel foundries between 1717 and 1735. He also started mining silver and gemstones in the Urals and Western Siberia. For his services, he and his brothers were made hereditary nobles. By the end of the eighteenth century, the family had become one of the richest in Russia, responsible for 40 percent of all Russian cast iron and members of the social elite.