Tom Heldal

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Nima Nezafati

Deutsches Bergbau-Museum, Bochum

Armando Marques-Guedes

UNL - New University of Lisbon

Gabriel Gutierrez-Alonso

University of Salamanca

Jocelyn (Josie) Hendrickson

University of Alberta

Juan Carlos Moreno Garcia

Centre National de la Recherche Scientifique / French National Centre for Scientific Research

María Antonieta Lorente

Universidad Central de Venezuela

Daniel Hershenzon

University of Connecticut

Mariam Rosser-Owen

Victoria and Albert Museum

Maja Vasiljevic

University of Belgrade

Michel Gregoire

Observatoire Midi-Pyrénées, Université de Toulouse III Paul Sabatier

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Berggrunn med avvikende kjemisk sammensetning: Metode for å etablere nasjonale datasett

23, 2020

Evaluering av framtidig behov og tilgang på naturstein i Buskerud, Telemark og Vestfold

Raw materials - you can't do well without them

Federal Institute for Geosciences and Natural Resources (BGR), Germany (1); National Laboratory o... more Federal Institute for Geosciences and Natural Resources (BGR), Germany (1); National Laboratory of Energy and Geology (LNEG), Portugal (2); Geological Survey of Denmark and Greenland (GEUS), Denmark (3); Geological Survey of Spain (IGME), Spain (4); Geological Survey of Norway (NGU), Norway (5) <br> <br>"Raw materials, you can't do well without them". This statement echoes the needs for a reliable raw materials supply chain. Awareness of raw materials is an essential element for the manufacturing industry, infrastructure, digitalisation, and others has significantly increased in this decade. So did the demand. The specific physical and chemical properties of the chemical element and the minerals they form make mineral raw materials special. The mineral surface reactivity for example, is an important parameter for pharmaceuticals [1]. COVID-19 refocused attention on the antibacterial behaviour of copper and copper alloys.

The Sagalassos Quarry Landscape

Sagalassos VI, 2008

From Hyllestad to Selbu: Norwegian millstone quarrying

Industrial-scale' millstone production in Norway dates back to at least AD 700. Recent detailed m... more Industrial-scale' millstone production in Norway dates back to at least AD 700. Recent detailed mapping in the Hyllestad and Selbu areas has identified extensive quarry landscapes, which together demonstrate the development in 'industrial scale' millstone production over a period of 13 centuries. Based on geological characteristics, traces of quarrying techniques and archaeological dating, it is possible to relate different stages within this history to technological development, population change, market demands and other influences from the surrounding society. Production at Hyllestad, which dominated the Norwegian millstone market from the pre-Viking Age, was based on carving of relatively soft but massive garnet-kyanite-muscovite schist directly from the bedrock in shallow quarries, a technique that was essentially similar to Iron Age soapstone extraction. A change to a more centralised and technologically advanced production in larger and deeper quarries occurred in the 12 th century, possibly introduced by professional stonemasons connected to the establishment of monasteries and churches. A marked decline in activity at Hyllestad after the High Middle Ages was followed by the rise of millstone production at Selbu in the 16 th century, based on wedging of more easily cleavable staurolite-biotite schist. It is likely that this dramatic change in market dominance was influenced by the partial collapse of social and trade structures following the Black Death and recurrent plague outbreaks throughout the late 14 th and early 15 th centuries, when the millstone trade was practically in ruins due to the small population size and the market was left open for 'newcomers' when population and trade recovered in the 16 th century. Equally important was the increasing demand for larger and more durable millstones caused by the gradual change from querns to water mills and from farm mills to village mills and commercial trade mills, a demand that could readily be met by the geological conditions that existed in the Selbu area.

Tom Heldal

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