Knalla gruvmuseum

Useful Information

Location:	Knalla, Askersund.
Open:	25-JUN to 10-AUG Mon-Fri 12-16. AUG Sun 12-16. [2007]
Fee:	Adults SEK 20, Children (0-14) free. Groups (10+): Adults SEK 15. [2007]
Classification:	Zinc Mine
Light:	Incandescent Electric Light System
Dimension:
Guided tours:
Photography:
Accessibility:
Bibliography:
Address:	Knalla gruvmuseum. E-mail:
As far as we know this information was accurate when it was published (see years in brackets), but may have changed since then. Please check rates and details directly with the companies in question if you need more recent info.

History

1857	mine opened.
1863	.
2004	mine acquired by Lundin Mining.

Geology

The Zinkgruvan deposit is located in the southwest corner of the Bergslagen mining district. The ores were deposited during the Proterozoic Svecofennian during an era of volcanism and sedimentation. The volcano-sedimentary complex consists of felsic metavolcanics with intercalated limestones and calcsilicates. The Zn-Pb-Ag ore bodies are tabular shaped and between 5 m and 25 m thick, intercalated in the upper part of the metavolcanic-sedimentary group. The deposit is 5 km long and at least 1,500 m deep.

Formed as sedimentary rocks, the whole area was folded by an orogeny which formed a series of small elongated basins. The basins are surrounded by mainly granitoid intrusions. The oldest granite intrusion are of the age of the sediments, others are younger. High pressure and temperature caused the metamorphization of the whole pack, which transformed the volcanics into metavolcanics and the sediments into metasediments. Today the ore deposit strikes mainly east-west and dips towards north. An almost vertical fault splits the ore deposit into two major parts, the Knalla mine to the west and the Nygruvan mine to the east.

The ore is mostly sphalerite and galena. It contains layers of quarzitic metatuffite and calcsilicate rock.

Description

The Knalla gruvmuseum is an open air museum showing the 150 years of zinc mining at Zinkgruvan. It has numerous miining related building, head frames and machinery. There is a working blacksmith, a mine train and the still working elevator gear. The museum has a photo exhibition, a geology exhibition with a huge model of the mine, a mineral museum, and a curiosity exhibition.

Zinkgruvan is a still working mine, which has been in production continuously since 1857. The mine produces zinc, with a certain amount of lead and silver as by-products. It is at the moment one of the largest zinc mines in Sweden, and most profitable as the cost per ton zinc is very low. But the estimated reserves will only last for 10 years, then the mine will be exhausted. Lundin Mining, who operates the mine, tries to increase the life of the mine by exploring surrounding ores, which could cause a change to copper mining in the future.