i have a rock of zoos about 6 inchs by 4 inches. they are mostly all green and then there is an individual zoo that is half red and half green. i mean right down the middle, it splits, one half is green and hte other half is red. it looks like someone took a razor and split 2 zoos and stuck them together. has anyone else heard of this and what could have caused this. it is the coolest zoo ive ever seen and if it is as rare as im thinking, i might break that piece and try to grow some more of them. any thoughts would help