Sun-bow?

This was the wildest thing; a rainbow around the sun. It formed a perfect circle and changed in intensity. At one point, the area inside the circle looked almost black as if some eclipse were in progress. Another time, it looked like a lovely rainbow of various colors. Then the whole thing just blew away. It was a ring of clouds, I guess; as they separated, the circle just disappeared.

We couldn't find a camera that would capture the entire thing so these were the best photos we could manage.