Back in 2005, when I was obsessed with Flickr, I played around a lot with the images in the Squared Circle group. These images are all of circular things, but are otherwise uncorrelated.
One of the things I tried was averaging handfuls of these images together, so that the individual features would fade away, and the common features - the circle would remain. The result looks likes this:
I call these "Bronze Shields".
My observation that most of these shields were orangish in color led to my closer examination of the Emergent Orange effect.