This was a great choice for this challenge. Just echoing what KarenNfld said, I would bet that putting a medium or high contrast curve on this with slightly increased saturation would really make this pop. Awesome patterns overall.
I don't know how long it took you to create this but it is unique. I like all of the different colors that you managed to include. There is also a lot of rythm
Probably the only shot in the challenge where I am going to support the randomness of your subject. You did a brilliant job showing the variations that nature has added to the simple shell pattern.
Absolutely fantastic! One of my favorites so far. The randomness and chaos of the shells is so strong, but yet my eye can pick up the patterns all over the place, even in the upside down foreground shell. Very creative, hope to see this one do well. Kudos.