Items having an established date, such as dated coins or buildings, or ceramics of known manufacture are most often used.
By itself, a cross-dated chronology does not give absolute dates, but it may be calibrated by reference to other dating methods.
If in culture A an object produced by culture B is found, A must be contemporary with, or later than, B.
The term cross-dating ought strictly to be used only when an object of culture A is also found in proved association with culture B, when overlap of at least part of the time span of each is proved.
Finns constitute the majority of the citizens of the Republic of Finland, which has a Swedish-speaking minority as well as Saami (Lapp) and Rom (Gypsy) minorities.
While language was a highly divisive issue as late as the 1920s and 1930s, many Finnish speakers now recognize the value of Swedish for communicating with other Nordic countries.
Last year, a female governor of one rural Swedish province requested that the government look into this situation, investigate abuse and perhaps even limit the number of Thai women permitted into the country.
Between September and April, Iceland is treated to a magnificent natural display: the phenomenon of aurora borealis, named after the Roman goddess of dawn, Aurora, and the Greek name for the north wind, Boreas. Due to its position on the Mid-Atlantic ridge, Iceland is one of the most active volcanic regions in the world.
The basis of cross-dating is the occurrence of finds in association.
The assumption is that a particular type of artifact, for example a type of sword, when found in an undated context will bear a similar date to one found in a dated context, thus enabling the whole of the undated context to be given a chronological value.
Sweden is one of a few countries where there is now a second and third generation Thai community which still maintains very close links with Thailand.
However, the increased levels of younger Thai women now entering Sweden has now become a political issue.