New findings on how strontium enters humans and on mobility from research at the medieval Hamina cemetery in Ii

January 8/2021

A recent study published in the scientific journal Archaeological and Anthropological Sciences examines human mobility at the Hamina cemetery in the community of Ii in the 15th and 16th centuries. It is one of the most significant graveyards in the northern part of Fennoscandia, owing to its size and its well-preserved human bones. It has been extensively researched and is the subject of a book and numerous scientific articles.

In the study, which was published in December, whose main researcher was Maria Lahtinen-Kaislaniemi, a researcher at the Finnish Food Authority, isotope methods were used to study the origins of people buried at the Hamina cemetery in Ii in the north of Finland. Objects and coins found in the burial ground suggest contacts far away in Karelia and Sweden. However, goods can move even if people do not.

“There were also indications of mobility in the diet of one person, which deviated from the others, discovered in a previous isotope study on diets. That person's diet had included considerably more agricultural products compared with the local people, who mainly ate fish”, Lahtinen-Kaislaniemi explains.

This study focused on the human remains themselves, from which it is possible to directly extrapolate the mobility of the person being studied. An oxygen and strontium isotope signal from the person’s environment in the time that the teeth were growing is recorded in the tooth enamel. By analysing it, it is possible to deduce if these people were in the area already as children.

The methods used in the study are still young in Finland. For this reason, it has been necessary to modify the methods to suit this environment. Finland's bedrock is old by European standards, and the ground that covers it was transformed by the Ice Age. These factors affect the composition of the strontium isotope, also in animals and plants.

“We also learned from the study that precise results cannot be obtained without more detailed development of methods. However, it appears that individuals with an exceptional diet also had an exceptional composition of oxygen and strontium isotopes in their tooth enamel. The young woman in question was probably from what is now Sweden or Finland, but much further south”, Lahtinen-Kaislaniemi says.

The study was conducted as a collaborative effort between the University of Helsinki and Durham University.


Lahtinen, M., Arppe, L. & Nowell, G. Source of strontium in archaeological mobility studies—marine diet contribution to the isotopic composition. Archaeol Anthropol Sci 13, 1 (2021). DOI:

Further information:

Researcher Maria Lahtinen-Kaislaniemi, Finnish Food Authority, tel. +358 50 339 4493