Dannemora mine
Encyclopedia
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.
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.
Throughout the mine's history, it had problems with water being situated by a lake. A pile-dam was built during the 17th century, and water- and wind-powered pumps were used. In 1728, at the initiative of Mårten Triewald
, a steam-driven pump was installed, a Newcomen engine, the first in Sweden, but it was never a success. The failure was probably due to technology, which worked flawlessly in England, but was new to Sweden and was run by inexperienced staff. During the 1750s, it blew away two weirs and this destroyed a blast furnace, a mill and two sawmills. Despite a newly built dam, the mines were flooded in the spring flood of 1795 and it took until 1815 before the situation became normal. in 1805 a new steam engine of 10 horsepower was installed.
During the century 1770-1870, production was between 15,000 and 20,000 tonnes. In the 1870s, it rose to 40,000 tonnes and exports of pig iron from the Österby ironworks became significant. In order to facilitate shipments of ore Dannemora Hargs Railway was built in 1878. During the 20th century, production was 50,000 tonnes, but a strike in 1927 stopped its operation entirely. Only in 1935 was it resumed. 1955 a new facility, with sorting plant and concentrator was finished and the annual production reached 600,000 tons. During the latter part of the 1970s, output decreased but still amounted to about one million tonnes of crude ore, of which the bulk was exported.
Shareholders of Dannemora mines had declined since the late 19th century through closures and mergers. In 1937 the four remaining owners (Fagersta Bruk, Iggesunds Bruk, Hargs Bruk and Stora Kopparbergs Berglag) formed AB Dannemora Mines. In 1974 Stora Kopparberg became the sole owner of the Dannemora mine. During the crisis that hit the Swedish steel industry in the late 1970s, however, that the state SSAB was forced to take over the mine only four years later.
Dannemora, Sweden
Dannemora is an old mining town and a locality situated in Östhammar Municipality, Uppsala County, Sweden with 238 inhabitants in 2005.-Dannemora mine:...
was one of the most important iron ore mines in Sweden. The mine was closed by its owners SSAB
SSAB
SSAB Swedish Steel AB , or simply SSAB is a Swedish company, formed in 1978 and specialised in processing raw material to steel. Industrivärden is the largest shareholder.-Swedish operations:...
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
Oregrounds iron
Oregrounds iron was a grade of iron that was regarded as the best grade available in 18th century England. The term was derived from the small Swedish city of Öregrund. The process to create it is known as the Walloon method....
by the Walloon process (using a blast furnace
Blast furnace
A blast furnace is a type of metallurgical furnace used for smelting to produce industrial metals, generally iron.In a blast furnace, fuel and ore and flux are continuously supplied through the top of the furnace, while air is blown into the bottom of the chamber, so that the chemical reactions...
and finery forge
Finery forge
Iron tapped from the blast furnace is pig iron, and contains significant amounts of carbon and silicon. To produce malleable wrought iron, it needs to undergo a further process. In the early modern period, this was carried out in a finery forge....
), such as Österby
Österbybruk
Österbybruk is a locality situated in Östhammar Municipality, Uppsala County, Sweden with 2,230 inhabitants in 2005.- References :...
and Leufsta (now Lövsta
Lövstabruk
Lövstabruk is a village built as a small city on a common in the parish of Österlövsta, Tierp Municipality, Uppsala County, Sweden. In 2005 it had a population of 107, compared to some 1300 at its height during the 18th century. Lövsta is derived from lösta, an old Swedish word for glade...
). Their products were particularly pure iron
Iron
Iron is a chemical element with the symbol Fe and atomic number 26. It is a metal in the first transition series. It is the most common element forming the planet Earth as a whole, forming much of Earth's outer and inner core. It is the fourth most common element in the Earth's crust...
, due the manganese
Manganese
Manganese is a chemical element, designated by the symbol Mn. It has the atomic number 25. It is found as a free element in nature , and in many minerals...
content of the iron ore. This made it the best material for conversion to blister steel, the main variety of steel
Steel
Steel is an alloy that consists mostly of iron and has a carbon content between 0.2% and 2.1% by weight, depending on the grade. Carbon is the most common alloying material for iron, but various other alloying elements are used, such as manganese, chromium, vanadium, and tungsten...
made in Great Britain
Great Britain
Great Britain or Britain is an island situated to the northwest of Continental Europe. It is the ninth largest island in the world, and the largest European island, as well as the largest of the British Isles...
between the 1610s and the 1850s. The mine has a depth of 640 metres.
History
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
Sheffield
Sheffield is a city and metropolitan borough of South Yorkshire, England. Its name derives from the River Sheaf, which runs through the city. Historically a part of the West Riding of Yorkshire, and with some of its southern suburbs annexed from Derbyshire, the city has grown from its largely...
. 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.
Throughout the mine's history, it had problems with water being situated by a lake. A pile-dam was built during the 17th century, and water- and wind-powered pumps were used. In 1728, at the initiative of Mårten Triewald
Mårten Triewald
Mårten Triewald , sometimes referred to as Mårten Triewald the Younger, was a Swedish merchant, engineer and amateur physicist....
, a steam-driven pump was installed, a Newcomen engine, the first in Sweden, but it was never a success. The failure was probably due to technology, which worked flawlessly in England, but was new to Sweden and was run by inexperienced staff. During the 1750s, it blew away two weirs and this destroyed a blast furnace, a mill and two sawmills. Despite a newly built dam, the mines were flooded in the spring flood of 1795 and it took until 1815 before the situation became normal. in 1805 a new steam engine of 10 horsepower was installed.
During the century 1770-1870, production was between 15,000 and 20,000 tonnes. In the 1870s, it rose to 40,000 tonnes and exports of pig iron from the Österby ironworks became significant. In order to facilitate shipments of ore Dannemora Hargs Railway was built in 1878. During the 20th century, production was 50,000 tonnes, but a strike in 1927 stopped its operation entirely. Only in 1935 was it resumed. 1955 a new facility, with sorting plant and concentrator was finished and the annual production reached 600,000 tons. During the latter part of the 1970s, output decreased but still amounted to about one million tonnes of crude ore, of which the bulk was exported.
Shareholders of Dannemora mines had declined since the late 19th century through closures and mergers. In 1937 the four remaining owners (Fagersta Bruk, Iggesunds Bruk, Hargs Bruk and Stora Kopparbergs Berglag) formed AB Dannemora Mines. In 1974 Stora Kopparberg became the sole owner of the Dannemora mine. During the crisis that hit the Swedish steel industry in the late 1970s, however, that the state SSAB was forced to take over the mine only four years later.