In this work, we investigate crystal structure of delafossite-type oxide CuFe1-x(Ca, Mg)(x)O-2 (0 <= x <= 0.04). It's known to induce a distortion in the structure, there is an important variation in the two lattice parameters a and c because of the big substitution of biunique radius of Ca2+ and Mg2+ (r(ca)(2+) = I angstrom, r(Mg)(2+)= 0.74 angstrom). Magnetic susceptibility measurements show a magnetic dilution for Ca-doped simples and an amplification of x with Mg-doping. Temperature dependence of the dielectric permittivity for CuFe1-x,MgxO2 present an amplification of is an element of ' at T-N2 = 9.1 K (C) 2014 Elsevier Ltd. All rights reserved.