Light stone is hidden under leaves, moss and forest floor: shimmering white, marbled beige or grey. A sword saw milled smooth edges four meters deep into the rock. Between Waldenbuch and Dettenhausen, a search was made for Stuben sandstone for the renovation work on the Ulm Minster. This first sample dismantling proved to be unsuitable.
A second near Dettenhausen promises more success. Geologists and stonemasons found a bank of sandstone at least five meters thick with even layers and no faults. Drill cores were taken, the material of which was put through its paces by scientists from the University of Stuttgart. They wanted to know: How porous is the stone? How frost and pressure resistant? For two months, the material was alternately shock-frozen to minus 20 degrees and heated to plus 50 degrees in order to simulate 150 years of weathering in fast motion. The result: "Very good grade". "There can hardly be a better, more handsome and more weather-resistant stone for the true-to-original renovation of the Ulm Minster and other Gothic masterpieces".
After all bureaucratic hurdles had been cleared and all approval procedures had been completed, the main dismantling began in mid-January 2016. Dismantling is to take place by 2026 during the vegetation dormancy period from the end of September to the end of March. 1000 cubic meters for 36 truck transports per year are to be dismantled. So 10,000 cubic meters in ten years: That is the maximum number of buildable blocks that can be removed from the Waldenbuch forest.
The Ulm Minster doesn't need quite that much. 50 cubic meters per year should be enough for the time being. But there are still plenty of other listed building sites in the country that have registered a need: the Frauenkirche in Esslingen, the Neckar Bridge in Tübingen, Hohenzollern Castle. The sandstone from Schönbuch should do the trick everywhere.