This paper investigates the microstructures, geochemistry, and hydrothermal evolution of gold-bearing pyrite and arsenopyrite from Carlin type, turbidite hosted gold deposits of China, intrusion related gold deposits, epithermal gold deposits and six orogenic gold deposits in the Archean Eastern Goldfields Province, Western Australia. Based on sulfide stability relations, the authors hold that the development of arsenopyrite alteration rims associated with late-stage visible gold formation was related to an increase in temperature and up to six orders of magnitude increase in sulfur fugacity. It is suggested that the transform from invisible to visible gold depends on the fluid conditions and chemistry.