Mikhailtech has a few copper CoolerMaster over for a roundup.

There are 13 fins on each side of the clip, 26 copper fins in total, and these fins stretch from one side of the heatsink to the other so they are 60mm long and about 25mm tall. But what is most interesting is the way the fins are attached to the base. They are not inserted or lead soldered, but copper based soldered as far as I can determine. I have closely examined the heatsink looking for anything that would resemble a hole in the base or a lead spot, but I found none, only copper. I guess this is why they called it a "pure copper" heatsink. The base of this heatsink is very smooth and it has an almost mirror shine.