Radula 5mm long from chiton 26 mm long. Llŷn, North Wales. March 2016.
Broad radula with extremely strong hard teeth of chitin mineralized with magnetite. Upper image of teeth on dorsal face, lower image of ribbon to which teeth attached. Anterior to left of image.
Posterior at right of image is where teeth commence formation, colourless as not yet mineralized.
In each row, a pair of major lateral teeth, the principal scrapers, are the most substantial and darkest with magnetite.
The paler, translucent, long, broadly tipped, major (third) uncinal teeth (1) have less mineralization as their function is to sweep up loosened food particles.
2: anterior of radula flanked by translucent whitish hyaline shield, folded under in this preserved specimen, extends laterally in life.
See SEM image 18Ac 18 Acanthochitona crinita for greater detail.

KEY ID FEATURES and similar species at: 01 Acanthochitona crinita