Pyrite is one of the common minerals in sediments and framboidal pyrites are densely packed，raspberry like，spherical aggregates of equigranular，micronsized crystals or microcrysts. Based on the previous studies of framboidal pyrites，we summarized formation mechanism of framboidal pyrites and discussed the significances of framboidal pyrites for palaeo?ocean redox conditions. At present，the genesis of framboidal pyrites is widely considered as two factors，namely abiogenic and organic genesis. The former held that organic matter or bacteria is involved in the formation of framboidal pyrite；the later insisted that supersaturated pyrite concentration is the necessary condition. Framboidal pyrite size，which is considered as an indicator of the redox condition，commonly is used to palaeo?ocean redox condition reconstruction. Although there is no consensus on exact criteria for identifing paleo?ocean redox by pyrite framboid size distribution，it is concluded commonly that framboidal pyrite size and the range of size is lesser in euxinic，and will become larger with oxyen increasing.
Zhou Jie Qiu Zhen Wang Hongyan Lu Bin Bai Wenhua Liu Dexun Tan Xin Jiang Zengguang. Formation mechanism of pyrite framboid and its research significance[J]. Chinese Journal of Geology, 2017, 52(1): 242-253.