A study of the laser-ionized and mass-separated neutron-deficient isotopes 176,177,179Au was performed using the Resonance Ionization Laser Ion Source and the Windmill detection setup at ISOLDE, CERN. New and improved data on complex fine-structure α decays of the three isotopes were deduced, providing insight into the low-lying levels in the daughter nuclei 172,173,175Ir. New information on the properties of β-decay daughter products 177,179Pt was also obtained. From the first in-source laser spectroscopy measurements of the hyperfine structure in the atomic 267.6-nm transition of 176Au, the nuclear magnetic moments for both high- and low-spin α-decaying states were deduced. Together with the values determined from the additivity relations, they were used to propose the most probable spins and configurations for both states. The α-decay branching ratios were determined as bα (176Auls ) = 58(5)% and bα (176Auhs ) = 29(5)%.