Dannemora mine

The Dannemora mine at Dannemora, Sweden was one of the most important iron ore mines in Sweden. The mine was closed by its owners SSAB in 1992. It may have been open since the 13th century, but the first documentary reference was in 1481. The mine supplied all the ironworks making oregrounds iron by the Walloon process (using a blast furnace and finery forge), such as Österby and Leufsta (now Lövsta). Their products were particularly pure iron, due the manganese content of the iron ore. This made it the best material for conversion to blister steel, the main variety of steel made in Great Britain between the 1610s and the 1850s. The mine has a depth of 640 metres.

Joachim Piper renewed the mining privileges at Dannemora in 1532 and devoted substantial resources to the mine, mainly producing iron but also other minerals. the ownership structure changed in 1545, and a dozen wealthy individuals entered as the owners, so that a number of Germans and even the king Gustav Vasa took part. The Germans were most interested in the export of pig iron but the King persuaded them to start production of wrought iron. It lasted only a few years and following a related bankruptcy, the king took over the operation fully.

Under 17th century. Dannemora iron had an uncontestedly high status among Swedish iron localities, especially in England where it was used in the steel raw material for tools, weapons, springs and other special purposes. A large part went to Sheffield. Thus Dannemora contributed to Sheffield's worldwide reputation as a steel city.

Around 1700 there were about sixty workers at Dannemora residents of the slum-like neighbourhoods around the mine. The number of workers who obtained their support from the mine is likely to be several hundred. In each mine large quantities of wood would used in mining, a method not abandoned until the 1730s. The reason for this was partly out of fear that gunpowder would be more expensive than wood, but also for danger's sake.

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