All of our landscaping at our apartment building involves rock beds. There's very little mulch here. We're apparently rock people. That works for me as I think the rocks look very nice. And they don't stink like mulch does. (I remember one year in college when there was a parking spot sized pile of mulch ready to go outside my dorm. It sat there for weeks and it just STAAAANK.)
For the most part on their own the rocks are pretty boring - some of them have some cool coloring or shape, but they're mostly forgettable. (Which is probably the goal in apartment complex landscaping.) There are a few here and there though, that are very unusual. This is one of them.