[4] He was enrolled as a student at the Swedish Board of Mines, aged sixteen, to study mineralogy.

Instead of continuing studying sciences, he started to shoulder administrative tasks at Larsbo bruk.

He did so as the head of the Tersmedens, serving the interests of his noble family in the assembly of the feudal estates of Sweden.

From 1760 to 1762, his younger brother, Carl, shouldered the role as representant of the Tersmedens at the Riksdag of the Estates.

On 22 September 1743 Tersmeden married Magdalena Elisabeth Söderhielm, also known as Lona Lisa, at World Heritage Site Engelsberg Ironworks.