Mother Of Pearl

I'm pretty proud of myself on this one. Someone in my office was showing me the glass beads she's begun making (having taken it up as a hobby), and one of them had a certain pattern on it that made me go: "Ooo! If you can do that, you should make a bead that looks like mother-of-pearl.

Then another person in the office asked, "what's mother of pearl?" And as a thoughtful look crossed my face, I reeled off this monstrosity in one go:

"It's the glossy, lustrous, often iridescent patina that coats the inside of a seashell. For shellfish that make pearls, the secretions accrete around irritants, encasing them in a hard coating that won't chafe the sensitive flesh of the mollusk."

There was a moment of silence, and then everyone dissolved into hoots of derision, repeating choice portions giddily in high-pitched British accents. What can I say, I deserved it, but I still say that's a pretty sweet off-hand definition!