That's not what a sun dial looks like, actually. I know you're seeing those little stripes and it's reminding you of such, but it's not. The first picture was enough to ID it. I'll bring some pics in.
Now I'm on the hunt for a large collonista as all of mine are little tiny microscopic ones. It's actually a great question, yet the only way I know how to make sense explaining it, is with pictures. I WILL find one... it would actually be great to add that comparison to my hitchhikers guide.