collum, those are remarkable rocks, they make me so very curious, what are they, can you explain some more?
In the netherlands we don't have rocks, or, better, no rocky grounds, only some in the very south and east. The rest is all alluvial, sediments from rocky Germany and Switserland. But during the ice-ages the scandinavian glaciers brought some real big stones, collecters-items. I don't have images from them. So, some summers ago in an Belgian green river I was busy with imaging the reflecting greens. Between the green a rock, hardly a quality-image, although the green is nice:
[attachment=20176:greenriverrock_1.jpg]