Jahrhunderts aus Europa als Quellen zur Handels- und Währungsgeschichte ('scales and weights from medieval Schleswig: finds from the 11th to 13th centuries from Europe as sources for trade and monetary history') is a 1997 monograph by Heiko Steuer.
[1] Chapter 1 surveys the history of research and gives a detailed presentation of the monetary context of Steuer's chosen region and period, Schleswig in the eleventh to thirteenth centuries.
Based on Byzantine and Arabic models, the invention of the folding scale reached its peak in the second half of the 9th century around Russia and Haithabu, the predecessor settlement of Schleswig.
In summary, the author sees the scales of types 7 and 8 from the eleventh to thirteenth century as characteristic of an advanced phase of the weight money economy, although the typological distinctions are of secondary importance.
A further comparison with the scales of type 3 shows a clear increase in the length of the bars between the 10th and 11th/12th centuries, which indicates that the masses to be weighed became heavier during this time.
The relatively small number of scales preserved and their widespread use by merchants and travelers also hinder systematic localization of production locations.
[2] Chapters 8 and 9 are short, addressing two special cases from Schleswig: two triangular weighing pans that belonged to money scales, and three bone balance-beam fragments.
As well as in book miniatures, on copper engravings, paintings and altarpieces, representations of scales can be found on church portals, reliquaries, candlesticks and stained glass windows.
These depictions sometimes comes from areas that lack archaeological finds, such as central Europe, and pictures from the 11th to 13th centuries help to date the twelfth-century transition between scale types 7 and 8.
[2] In Chapter 11, Steuer describes and analyzes all 22 weights found in Schleswig, comparing them with similar finds from other places, taking into account a large number of earlier studies.
The chapter closes by analysing three weights from steelyard balances, a type found in Antiquity, but which in the Middle Ages were apparently only used to weigh heavy commercial goods.
However, taking into account the weights found, it becomes clear that the upper limits of the load capacity were often not adhered to, with the weighing range increasing from the tenth to the thirteenth centuries.
A special feature of this time are the so-called Seiger, steelyards or Kippwaagen (tilting scales) made of metal or bone, used for checking the correct weight of coins in circulation.
Based on the different composition of the silver treasure finds and the changing type spectrum of scales and weights, the author comes to a division into three successive phases: 1.