This page of the Building Stone website visits the Mosel (or Moselle in more French tones) Valley in western Germany. We'll follow the Mosel from Trier (almost in Luxemburg) to Koblenz (at the confluence of the Mosel and the Rhine). Specifically, we will visit many buildings of slate, an unusual building stone, and look at the them in the context of outcrops along the Mosel Valley.
We'll begin in the village of Thörnlich with this house. In addition to the slate, note the red sandstone that frames both the windows and the niche for the statue:

 Here's a view of the slate itself. Note the irregular elongate stones - essentially slivers of slate - dictated by the cleavage of slate into subplanar pieces.