A new kind of black nephrite was found in Dahua Yao Autonomous County, Guangxi Zhuang Autonomous Region. In this paper, gemological, petrological and mineralogical characteristics of the nephrite were studied. The results show that the fine and moist nephrites with micro-interwoven fibers and micro-prismatic textures are composed mainly of actinolite and ferroactinolite, and contain typical minor mineral stilpnomelane together with pyrite and pyrrhotite. As a new genetic type of dark nephrite deposit, the Dahua black nephrites occur in the inner contact zone between diabase and surrounding carbonate rocks and were formed by hydrothermal metasomatism after skarnization. The Dahua black nephrites have almost the same gemological characteristics as the black nephrites from other places, whereas the Dahua black nephrites with slightly higher density are iron-richer in composition and consist mainly of minerals with high iron content. The color of Dahua black nephrites is caused by actinolite-ferroactinolite with high iron content.