(You say it CUE-lit.)
The culets I possess are tiny, I must admit. And they're inside a cage of platinum.
So what are culets?
A culet is the small flat surface at the bottom of a gem. It's there to make it less likely that the stone will get damaged, as it might if it got knocked on a pointy bit.
You can see a culet at the bottom of this diagram of the facets of a gem. It's worth looking the whole diagram, because the names of the facets are gorgeous.
Of course you may not have a diamond handy - and if you have, it may not have a culet - but there's still some faint hope of spotting one because a culet is also one of the plates on a suit of armour that cover the back from the waist downwards.
Except that...um. Yes, sorry. People in suits of armour aren't to be seen all over the place, I must admit.
It really would be easier to talk nicely to a married or engaged lady, wouldn't it. Or have a look in a jewellery shop.
Anyway, there we are. Two culets linked by...
Spot the frippet: culet. This word comes from the French cul, from the Latin cūlus, which are both slightly rude words for bottom.