it sorta looks like obviously this object has another state in which something was bashing against the left side of that thing

and the top part is black anodised aluminium, and it looks fairly big, i mean, the metal content is large, ie, the top section is probably CNC machined and anodised

i'm betting this is some part of one of these fancy tablets or laptops or similar, it's hard to tell by scale but my guess is that cavity is under half an inch wide (you know probably your phone has macro capability?)