That is not a pearl of an idea.

That is not a pearl of an idea.

A pearl is a rare beautiful thing, when grown in nature. Hat off to Jesper on adlist who found these gems.
when in Adland however, a pearl is a prop to use in order to describe a rare beautiful thing.
and it's not rare at all as an idea.
Ok, for the water guys, I can see how they reached this conclusion. Pearls after all are natural [when not farmed], and take a long time to create, just like a pure spring water.
There is however nothing natural about a Mercedes SL. And it doesn't even have mother-of-pearl dashboard. Mercedes SL could have done better than this, as a toycar stuck in an oyster can be interpreted a few ways, not all of them good, and the 'pearl'-thought is plain wrong for a car which is not natural in any respect.
There might however be some french expression or idiom visualised here... Don't know the language so I can only guess.

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