The ability to predict rock failure is desirable for the prevention of disasters in mines. The acoustic emission (AE) method is a well-known tool for monitoring fracture growth in rock masses that is used to help ensure safety during excavations. In mines, AE can indicate the location of fractures and damage zones. If AE could be used to detect the initiation and extension of fractures in rock masses and determine their precise source locations, that information would be helpful in forecasting the locations of rock failure. A study of AE in the Ezulwini gold mine in South Africa has been conducted under the Japan–South Africa collaborative project titled “Observational studies to mitigate seismic risks in mines” [1, 2], in which a large number of events have been detected around the mining front. In this paper, we report on the determination of the source location of AE by the joint hypocenter method and multiplet analysis, and we delineate structures in the AE cloud.