Three compounds, i.e. CuMnAs, CuMn3As2 and Cu2Mn4As3, are known to be stable in the concentration triangle of copper-manganese-arsenic. Much attention was payed to CuMnAs adopting both orthorhombic and tetragonal structures, provoking significant experimental and theoretical research due to the promising spintronic applications [1] and non-trivial physical properties [2]. We studied the formation of both the tetragonal and orthorhombic CuMnAs phases during the crystallization of CuMnAs-melts with various deviations from stoichiometry. The areas of the concentration triangle with predominant tetragonal or orthorhombic CuMnAs phases were determined. Tetragonal and orthorhombic CuMnAs powder samples, obtained by the melt crystallization method, were studied by means of X-ray (XRD) and neutron diffraction (ND). The obtained refined lattice parameters for the tetragonal phase a=3.798(1) Å, c=6.342(2) Å for XRD and a=3.800(1) Å, c=6.343(2) Å for ND agree well with the single crystal data. For the orthorhombic phase the refined lattice parameters are: a=6.593(1) Å, b=3.866(1) Å, c=7.323(1) Å. The magnetic and electrical properties of polycrystalline samples of the orthorhombic and tetragonal CuMnAs have been studied as well. All samples demonstrated a p-type metallic conductivity. Magnetic susceptibility behavior of the orthorhombic phase indicates an antiferromagnetic interaction of manganese ions in CuMnAs, thus, confirming previous results [3]. For homogeneous samples of the tetragonal phase, the antiferromagnetic behavior of the magnetic susceptibility is characteristic. In some samples we have detected the inclusions of MnAs, which significantly influence magnetic and electrical properties. Namely, the character of the temperature dependence of magnetic susceptibility was changed from the AF to FM and, moreover, a kink on the temperature dependence of the electrical conductivity was observed at the para/ferromagnetic transition of MnAs, TC=318K. A comparison of our results of magnetic susceptibility for homogeneous tetragonal CuMnAs samples with those published earlier [4] leads us to the conclusion that the FM behavior of magnetic susceptibility obtained in [3] originates from MnAs inclusions.  Acknowledgments: The authors thank HZB for the allocation of neutron radiation beamtime.