Silverberg i Järnbärarland. Bergshanteringens begynnelse i ljuset av Schmidt Testhammardateringar

Sammanfattning: This dissertation describes the development of a new method for relative datings of mines and quarrries ofpreviously unknown age. The method is known as the Testhammer dating method, and uses an instrument,Schmidt's Testhammer, originally invented in 1948 for measuring the solidity of concrete. Since the 1960s, theTesthammer has been utilised within different archaeological and geological projects around the world.During the 1990s, the method has been used at Umeå University for relative datings together with otherdating methods such as lichenometry. Since 1994 it has been possible to use the Testhammer as acomprehensive dating method due to the invention of the Differential test.The main object for testing is the Sala Silvermine together with a large number of small abandoned minesin the Sala mining area. The results of the datings indicate that the mining industry in the Sala area is mucholder than previously thought, starting in the 11 th century AD. As a comparison, a well-known medievalsilvermine, Stollberg (Väster silvberg), in the Dalama province, has been investigated using the samemethod.