A research team at the university's geological institution has studied four stones found just outside the small village of Kitkiöjärvi in Pajala municipality.
The first stone was found in 2017 by a Finnish master's student. The following year, further finds were made by a local amateur geologist.
Analyses of mineral grains in the stones show that they come from a previously unknown meteorite impact 659 million years ago, the university writes in a press release.
"They originate from a crater that must be the oldest known crater in the country," says geologist researcher Carl Alwmark, who led the study, according to a press release.
However, the researchers have not been able to find the crater itself.
"Our results confirm that there are undiscovered craters in northern Sweden. Now, the detective work remains to find the elusive crater that is lurking somewhere outside Kitkiöjärvi," says Carl Alwmark.
