Interesting spinning brooch

[Bron]

This is an interesting sterling brooch, and I need help figuring out the country it comes from. In addition to the Letter?, Crown, and Horse, it is marked 925. But what makes it interesting is that the large center portion of the pin spins so that it is jet black on one side, but if you open the pin back you can spin the center oval to show the reverse side, which can hold a picture or a photo. It is like an elaborate mourning pin.