How does holy critical damage work?

Does anyone know what effect exactly does the Sacred Scissors provide? Do they just apply your normal crit rate to all holy damage or create a new %? And also does the +crit chance from Blacksmith's Hammer apply to the holy crit chance? Does the Anvil effect also apply to crit holy damage (90% sure yes but just in case asking)? Any anwers to any of those questions are greatly appreciated.