Kupferbergwerk Grube Wilhelmine Sommerkahl

Useful Information

Location:	Wilhelminenstraße 67, 63825 Sommerkahl. (50.069122, 9.271612)
Open:	APR to OCT Sat, Sun only with reservation. [2023]
Fee:	Adults EUR 5, Children (5-16) EUR 2.50. [2023]
Classification:	Copper Mine
Light:	Incandescent Electric Light System
Dimension:	T=9 °C.
Guided tours:	MinAge=5.
Photography:	allowed
Accessibility:	no
Bibliography:	Joachim Lorenz (2022): Das ehemalige Kupferbergwerk der Grube Wilhelmine in Sommerkahl im Spessart - jetzt Besucherbergwerk, online
Address:	Kupferbergwerk Grube Wilhelmine Sommerkahl, Wilhelminenstraße 67, 63825 Sommerkahl, Tel: +49-6024-632552. 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

1542	first written mention.
1870	taken over by merchant Justus Matthäus Bastert from Frankfurt am Main and underground mining started.
1923	mining ended.

Geology

The deposit itself is a polymetallic hydrothermal fracture-bound deposit with sulfide ores. The Schöllkripper gneiss is part of the Variscan basement and was formed in the Carboniferous around 335 million years ago. A granite diapir underwent metamorphism due to high temperatures and pressures and transformed into muscovite-biotite gneiss. In the Jurassic, when the gneiss was still overlain by sediments, fissures opened in the rock through which hydrothermal solutions flowed, hot waters containing sulfur and silica. This hot water dissolved copper from the overlying sediments, presumably Rotliegendes and/or Kupferschiefer (Lower Triassic). It is not known which layers were involved, because they have been eroded in the meantime. Through convection, the minerals reached the fissures in the gneiss and were precipitated there together with barite and quartz in the form of sulfidic copper ore minerals. Such filled fissures are called hydrothermal veins. Only in the veins where larger quantities of copper ores crystallized as a result of the geological processes mining was worthwhile.

Description

The copper mine Grube Wilhelmine Sommerkahl is special because it is one of the few mines in the Spessart and also one of the quite rare copper mines in Bavaria. The deposit is polymetallic, which means that various metals have been found, but copper ores probably played the biggest role in the mine's economic success. The mine was first mentioned in documents in 1542. At that time, minerals containing iron and copper were mined in open pits, the result being the small quarry where the entrance building is located today. The merchant Justus Matthäus Bastert from Frankfurt am Main took over the mine in 1870, and proceeded to underground mining. Depending on the thickness and copper content of the vein, this was either very successful or not. He had the ores processed for smelting in a nearby leaching plant. He also founded a company for this purpose, the Spessarter Kupfergruben- und Hüttenverein zur Justushütte bei Aschaffenburg. In the Justushütte, he smelted the copper into dams, which are ingots of raw copper.

The show mine does not have regular opening hours at present, it is necessary to book visits. For groups it is possible every day, individual visitors should join one of the guided tours on weekends. In any case, it is probably best to contact first via the contact form on the website. Usually, the website also shows already scheduled tours with free places, mostly for the following weekend, for which you can easily register by e-mail. Guided tours take place all day on Miners' Day, Open Monument Day, and Geotope Day. Registration is not necessary on these days.

There is a yellow and red exhibition building at the mine, which is the meeting point and first stop for the guided tours. It contains the mining exhibition and is also the clubhouse. The permanent exhibition includes a mineral display, a model of the 23 m level, and working models of the processing methods used in copper ore mining, such as the stamp mill and screen ball mill. Much is hands-on, such as the feeler boxes, a Gezähe (mallet and chisel), and four different computer learning programs. There are also miners' lamps, a model of the Linkenbach round hearth, and a geological profile of the Vorspessart region.

The underground part of the tour visits the 23 m level of the mine, which has a total of four levels down to 70 m. Two widenings, called Oberbruch, one of which can be booked for weddings, a saiger and a tonnage shaft, two historical pit cages and copper minerals such as azurite, malachite, and copper vitriol can be seen here. Due to its age, the mine also already has dripstones, sinter crusts, small sinter basins (micro-gours), cave pearls and so-called soda straws, calcite tubes which are the beginning of stalactites.

The non-profit association, which runs the mine on a voluntary basis, is very active. Since 2021, with the help of a grant from the Kommunale Allianz Kahlgrund-Spessart, a mining forge in half-timbered construction has been built on the outdoor site. A mine without a forge is inconceivable, as the gear had to be re-sharpened daily and often repaired. Another project is the reconstruction of the historical winding shaft as a wooden model, which has now been completed. It is full-size and functional, one of the two pit cages can be walked on.