I'm glad you included the larger shell in a thirds position. It gives the eye a place to rest and take a break while looking at all the interesting texture you have going on. contrast looks pretty good. Maybe a tad more? But maybe not. I'm not much of a fan of borders but it might help in this case to keep me in the photo. Nothing elaborate just a little one. Good large dof and focus.
nice shot, it definitely has texture. i'd prefer it if it was cropped a little tighter so i could see more detail in the large shell. just my preference