NOT much to look at.

It was when we bought it. 
I was on one of my periodic "Wander, point, shoot" expeditions around the back garden when I spotted a bit of this. Two bits in fact, but 1/2 of them was easier to show/see.
How in the name of all things odd it/they became exposed I haven't a clue; but in the interests of my haphazard record keeping I thought I'd better "have" them before I unexposed them.