  Ce$_{3}$Bi$_{4}$Au$_{3}$ crystallizes in the same non-centrosymmetric cubic
structure as the prototypical Kondo insulator Ce$_{3}$Bi$_{4}$Pt$_{3}$. Here we
report the physical properties of Ce$_{3}$Bi$_{4}$Au$_{3}$ single crystals
using magnetization, thermodynamic, and electrical-transport measurements.
Magnetic-susceptibility and heat-capacity data reveal antiferromagnetic (AFM)
order below $T_N=3.2$ K. The magnetic entropy $S_{\rm mag}$ reaches $R$ln2
slightly above $T_N$, which suggests localized $4f$-moments in a doublet ground
state. Multiple field-induced magnetic transitions are observed at temperatures
below $T_N$, which indicate a complex spin structure with competing
interactions. Ce$_{3}$Bi$_{4}$Au$_{3}$ shows semimetallic behavior in
electrical resistivity measurements in contrast to the majority of reported
Cerium-based 343 compounds. Electrical-resistivity measurements under
hydrostatic pressure reveal a slight enhancement of $T_N$ under pressures up to
2.3 GPa, which supports a scenario wherein Ce$_{3}$Bi$_{4}$Au$_{3}$ belongs to
the far left of the Doniach phase diagram dominated by
Ruderman-Kittel-Kasuya-Yosida (RKKY) interactions. Using realistic many-body
simulations, we confirm the semi-metallic electronic structure of
Ce$_{3}$Bi$_{4}$Au$_{3}$ and quantitatively reproduce its local moment behavior
in the paramagnetic state.
