I have a feeling I missed the shedding since when I looked later in the afternoon it didn't look as pristine as it does here. Took a picture of the shell with my trusty Fujifilm F30 which is a macro genius. See the "next" image.
It sure looks like some kind of alien! Creatures that shed their skin are fascinating, especially when you find the skin they have grown out of. We do the same thing, but we shed a cell at a time.