Here's what Frostytech has been able to find out. The black 'ceramic coating' on the Xigmatek Dark Knight SD1283 Night Hawk Ed. heatsink is described as "high thermal conductivity metal surface treatment" by its manufacturer; SAU Applied Materials . SAU Applied Materials is a Taiwan-based company which primarily focuses on LED related thermal products, for example the coating on thisLED MR16 light. About all we can say with certainty is that a rough black surface coating increases surface area somewhat and radiates heat more efficiently than a shiny aluminum surface.