Actually, silavor, it was pointed out. The Alchemy Circle is the background of many things. Wiki, online store, character creation (when picking gender), some wallpapers, the boxes. It's all over the place.
@freakdaddy, I thought the same thing with the upper left corner, however a symbol (the one in the center of the circle) is in that corner twice.
I have also noted that symbol being in the Prophecies Circle a total of 4 times (center, twice in upper left, once in upper right) and once in the Nightfall Circle. Also, the circle that is in the "bubble" in the Prophecies Circle is also in the Nightfall Circle (although heavily covered) in the upper, middle area of the right side.
The star-like shape near Warrior in the Prophecies Circle is also in the Nightfall circle twice. Once in the bottom middle of the right half and right in the middle, at the top of the "list" of shapes.
There are other shapes in the Prophecies Circle that is in the Nightfall circle as well.