Thoughts on blueberry jam

What is going on with the "bedding"? To me it does look like a lot like tiny spheroids are all squished together, limited by bedding planes vertically and each other laterally. But as Nick pointed out earlier, they are of a different composition than the large spheres.

Is this an original texture.

But could they also be concretions? If the precursor of this rock were wind dunes, which are occasionally wet or dry, then heavy minerals would form some layers while other beds would be composed of light minerals. The heavy minerals (esp. magnetite, hematite, sulfides, etc..) would also form lag depsoits in troughs of ripples, interdune areas, and other areas.

During lithification (cementation/alteration) the large concretions form from larger mineral grains that are randomly(?) disributed in the rock. Smaller heavy grains in concentrated layers would also diffuse into the matrix, but not as far. I have seen some white interiors to the spheres.

Oh, I recently saw a piece of chocolate that someone had dropped on a ski slope. You could see a round diffusion halo as the square chocolate disolved into the snow. Didn't have a camera. Rats. It was pretty cool. Well, to a geologist, anyway.