Missing Hubcap

So funny story, I was turning onto one of the canyon roads in Sunol when I saw something in my rear view mirror. There were no other cars around so I knew that it was from me. It was one of my hubcaps rolling away. It popped off at such a speed that it went rolling back, then turned left, then hit a curb and had enough turning to it that it cleared the curb and flew down a ravine - never to be seen again. I went looking for it, but to no avail. It is gone. So now I'm missing two hubcaps, both on me back tires.