Gold occurs in conglomerate beds and in veins in a quartzite-conglomerate unit of the Jacobina series of Precambrian age in northeastern Brazil. The series is 8,000 m thick and includes pelitic schist and quartzite. The pelitic schist and the mafic and ultramafic rocks that intrude the series contain mineral assemblages corresponding to the amphibolite facies of metamorphism. Evidence of a placer origin for the gold may have been obscured by redistribution of the metal during metamorphism.

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