It reminds me of a little volcano or mountain or something. quite scarry.
Was that a dremel creation? Maybe just a big grinder?
Ive always had an idea for your blocks, so I'll just spill it now. Just for sake of testing, I was thinking of a hole drilled straight down into the "mountain top" with four holes drilled into the sides of the "mountain" so that a small amount of watter would be forced inside the copper comming out the bottom further turbulating the already turbular water