nacre

Nacre, the iridescent mother-of-pearl inside the shells of marine mussels and other mollusks, is exceptionally tough: it can deform without breaking.

A well-known example is nacre, which is used in jewellery because of its iridescent colours.

However, the exact processes and conditions that lead to nacre, a composite of biopolymers and platelets of crystalline calcium carbonate, are the subject of intense debate among experts, and different theories exist.

The mollusc deposits layers of aragonite and conchiolin, which together form nacre, also know as mother-of-pearl.

I see now that my myths — that I was spontaneously generated, or carefully selected, or launched like a girl-Moses of the North Sea — are nothing more than layers of nacre that my mind has applied to create a pearl out of the sharp-edged fact of my abandonment.