Unusual because ammolite is found primarily along the eastern slopes of the Rockies.
A couple of years ago I found a few ammolite pieces at the Castle Hayne NC quarry and posted photos of these on a different mineral board.  A few days ago I came across some more of this material.
Ammolite is an iridescent, opal-like organic or biogenic gemstone like amber and pearl.  Ammolite comes from the inner shell layer - the mother-of-pearl or nacre layer - of certain types of fossilized shells.
High quality specimens have an iridescent opal-like play of colors.  The most desirable gemmy colors are deep reds and greens.  Castle Hayne pieces aren't very gemmy and most are light violet and golden brown with some mix of other colors.  The ammolite weathers and oxidizes quickly to a dull to dark brown.  Rapid weathering makes it difficult to find colorful pieces at Castle Hayne.  A couple of photos of new finds are attached.  Ammolite doesn't cover the entire surface - there are areas where the grey to dull green matrix can be seen.