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在西格陵兰37亿年前上地壳岩带中的硫化物、硅酸盐和碳酸盐相含铁建造中,发现了伴有少量磁黄铁矿的铜硫化物。在氧化相含铁建造中,黄铁矿是仅有的硫化物,只有少量产出,在变质的玄武质凝灰岩中,发现过黄铜矿和磁黄铁矿薄层。变质达低级闪岩相,从而形成高温黄铜矿—方黄铜矿的结晶。随后的冷却,导致不混溶作用,使黄铜矿和方黄铜矿分离成片状,在一些地方与针状磁黄铁矿共同产出,方铅矿的铅同位素比值显示出硫化物和上地壳岩是同时代的产物。认为含铁建造和凝灰质闪岩中的硫化物属海底喷气成因。
Copper sulphides with a small amount of pyrrhotite were found during the sulfide, silicate and carbonate phase iron formation in crustal rock belts in West Greenland 3.7 billion years ago. Pyrite is the only sulphide in the construction of oxidized-phase iron, with only a small amount of output. In the metamorphic basaltic tuff, chalcopyrite and pyrrhotite were found. Metamorphism of low-grade amphibolite facies, forming a high-temperature chalcopyrite - side chalcopyrite crystallization. Subsequent cooling resulted in immiscibility, separating chalcopyrite and chalcopyrite into flakes, co-producing with acicular pyrrhotite in some places, and the lead isotope ratio of galena showing sulphide and Upper crustal rock is the product of the same period. The sulphides in iron-bearing and tuff amphibolite are thought to be of marine jet origin.