The Slate Museum in Haut-Martelange is an integral part of Luxembourg’s mining history. In today’s PISA Science Magazine, Olivier Catani explores the depths of the mine, which is open to guided tours – as long as they can keep the water out.
RTL Today has teamed up with PISA, the Luxembourgish science magazine, to reproduce their original videos in English for our site. Watch all English videos on RTL Play, or discover the wide range of subjects previously covered in Luxembourgish here (there are 13 seasons, mind you! We’ll try and catch up).
Our previous episodes covered the history of the tram, Luxembourg airport, explained how the coronavirus vaccine works, asked why traffic lights always seem to be red, investigated where our tap water comes from, looked at Luxembourg’s railways since 1859, took a dive into the Moselle Valley and its underground Dolomite mines and more…
For over 200 years, slate was extracted from the Grand Duchy’s land. The extraction left a big hole in the ground, large enough to hide an entire cathedral inside it. Time to dive down into this mysterious and fascinating world beneath our feet.
Slate is a fine-grained rock composed of clay or volcanic ash, and used for roofing, flooring, gravestones and gardening. It has been used for centuries, and even in Luxembourg the extraction process began many decades ago.
The access point was opened in 1943 as an entrance to the air-raid shelter, in the event that bombs would fall in the Second World War. Today it is the main entrance to the mine, which is open to visits.
The construction work on the underpass took three years to complete. Special attention was paid to lighting. In fact, the installed lights flicker rapidly, mimicking the lighting miners would have experienced several decades ago. Some may call this fake, but it really recreates the environment those hard workers were in.
But lighting is not the only challenge – so is groundwater. Water is constantly pumped out for the mine for it to remain accessible to tours. A big water pump, now no longer in use but active back in the days, is on display at the entrance.
In Haut-Martelange, 1 million cubic metres of stone were mined, and all that space filled up with water to a height of 12 metres. Quite literally a lake underground!
The mine has 23 chambers that go down to 168 metres. But what to do with all the waste the miners were left with, roughly 75-80% of all the material they mined? They decided to build dry stone walls.
These mines are less dangerous than the iron ore mines in southern Luxembourg. Not only were there spots with a sharp 160-metre drop, but communication was incredibly difficult between engineers and workers. There was always the risk of collapse or a deadly fall, the latter which sadly occurred several times.
The mine was shut down over 30 years ago, in 1986, but the Slate Museum has ways of bringing the old days back to the modern times. A large projector screens short film snippets of the workers in action, making visitors feel like a part of history.
The boss of the mine was August Rother, who ran the company from his office. He was a rich business man, owning a residence with 20 rooms and a walk-in closet, a real luxury back in the days. He used to ride his horse around the grounds to ensure business was going as usual. But there remained a big disparity between Rother and his workers.
The original office is still in tact, which is included in the museum’s tour. It even includes the original accounting books and typewriters. Back then, the concept of a monthly wage did not exist: Workers were paid per tonne.
The mine closed in 1986 due to the great competition from Spain and Portugal. But the history remains, and thanks to the restoration and maintenance of the local team, is accessible to us all.
The Museum can be visited all week, apart from Mondays. Check out Ardoise.lu for more information.