A stolen fragment of an affresco from the cave church of the Madonna degli Angeli has been recovered in Germany and returned to Matera. The article from the Art Journal explains the story here. My blog posting about the church is found here. An image of the fragment is shown below:
Here is a view of the church interior. The above affresco was taken from the figure directly left of the opening.
I painted a view of the ravine with the church several years ago. Madonna degli Angeli is on the hill to the right. Below is an image of the painting: