On 2 December 1719, miners discovered a dead man in the water-filled shaft known as Mårdskinnsfallet, in a part of the mine that had not been used for a long time. Both legs of the dead man were amputated and missing, When the body was raised to ground level, it began to dry and became "hard as wood" according to a contemporary description. When the naturalist
Carl Linnaeus visited, he noticed that Fet-Mats was not petrified but just covered with
vitriol, a substance now commonly known as the pesticide
copper sulfate. Linnaeus stated that as soon as the vitriol evaporated, the body would begin to decay. That proved to be correct. , inscribed in Swedish as follows: "In memory of the miner Mats Israelsson who died while working at the Falun Mine in 1677" However, Fet-Mats Israelsson's body remained on display for thirty years, until he was buried in Stora Kopparberg Church in
Falun on 21 December 1749. During renovation of the floor in the early 1860s, the remains of Fet-Mats were found again and exhibited in a display case, until he was finally buried in 1930 in the church's graveyard. ==In culture==