Abstract: A dielectric ceramic composition for microwave applications having the formula ##EQU1## wherein x, y and z are molar percentages and 10.ltoreq.x.ltoreq.22, 58.ltoreq.y.ltoreq.80 and 8.ltoreq.z.ltoreq.22, O<n.ltoreq.25, and x+y+z=100;M is at least one selected from the group consisting of Sr, Ca and Mg; andR is at least one selected from the group consisting of Nd, Sm and La.The dielectric ceramic composition may further contain at least one oxide selected from the group consisting of Cr.sub.2 O.sub.3, Fe.sub.2 O.sub.3, WO.sub.3, SnO.sub.2 and ZrO.sub.2 in the range of more than zero to 5 mole percent based on the total molar percentage of x, y and z and have a superior combination of properties, particularly a high dielectric constant, a large Q and a small .tau.f which adapt them especially to use at the microwave region (wherein Q is the reciprocal of dielectric loss tan .delta., i.e., Q=1/tan .delta.).

Abstract: A dielectric ceramic composition comprising a ternary system composition represented by the formula, aBaO.bTiO.sub.2.cWO.sub.3 (wherein a, b and c are percent molar fractions totaling 100, i.e., a+b+c=100; 17.ltoreq.a.ltoreq.21.5; 75.ltoreq.b.ltoreq.83 and 0.1.ltoreq.c.ltoreq.5) and characterized by an advantageous properties, particularly, high dielectric constant, large Q and small .tau.f. In the compositions, TiO.sub.2 may be partially replaced by ZrO.sub.2 and, optionally, MnO may be also included up to 3 mole percent based on the total molar amount of the foregoing ingredients. The dielectric ceramic compositions are especially, but not exclusively, useful in microwave applications because of the foregoing advantages.