Abstract: A piezoelectric ceramic composition represents a composition formula, (Pb.sub.u A.sub.1-u).sub.v {(Zn.sub.1/3 Nb.sub.2/3).sub.w (Sn.sub.1/3 Nb.sub.2/3).sub.x Ti.sub.y Zr.sub.z }.sub.2-v O.sub.3, where the symbol A is at least one component selected from a group consisting of La, Nd, Pr, and Bi, and u, v, w, x, y, and z are within ranges represented by the following Equations, characterized in that 0.1 to 3 mole percent of a Mn compound calculated in terms of MnO.sub.2 is added to said piezoelectric ceramic composition.w+x+y+z=1 [Equation 1]0.85.ltoreq.u.ltoreq.0.990.97.ltoreq.v.ltoreq.1.030.01.ltoreq.w.ltoreq.0.200.01.ltoreq.x.ltoreq.0.150.35.ltoreq.y.ltoreq.0.480.30.ltoreq.z.ltoreq.0.

Abstract: The present invention provides dielectric ceramics with less variation of temperature coefficient at a resonant frequency due to heating history during the sintering of ZrTiO.sub.4 and ZrO.sub.2 --SnO.sub.2 --TiO.sub.2 ceramics, and having a high unloaded Q value and a high dielectric constant, and a temperature coefficient at a resonant frequency which is widely variable as desired, and dielectric resonators using the dielectric ceramics which have a high unloaded Q value and a strong electrode layer. The main components of the dielectric ceramics may be expressed by the formula: xZrO.sub.2 --yTiO.sub.2 --zA.sub.(1+u)/3 B.sub.(2-u)/3 O.sub.2 wherein A denotes at least one component selected from the group (A) consisting of Mg, Co, Zn, Ni and Mn, B denotes at least one component selected from the group (B) consisting of Nb and Ta, and x, y, z and u (x, y and z are molar fractions and u is a value within the range from 0 to 1.90) have the relation of x+y+z=1.0, 0.10.ltoreq.x.ltoreq.0.60, 0.20.ltoreq.y.ltoreq.

Abstract: The invention provides a dielectric ceramic including as the main component a complex oxide formed of both Zr and Ti, at least one component selected from the group (A) consisting of {Mg, Co, Zn, Ni and Mn} and at least one component selected from the group (B) consisting of {Nb and Ta} and a TE.sub.01 .delta.-mode dielectric resonator including the dielectric ceramic, and also the invention provides a dielectric ceramic composition expressed by Formula (a):xZrO.sub.2 --yTiO.sub.2 --zA.sub.(1+w)/3 Nb.sub.(2-w)/3 O.sub.2Formula (a)wherein A denotes at least one component selected from the group (A) consisting of {Mg, Co, Zn, Ni and Mn},x, y and z denote molar fractions ranging from 0.10 to 0.60, 0.20 to 0.60 and 0.01 to 0.70, respectively, and have the relation represented by Formula (a):x+y+z=1 Formula (a)and w denotes a value of 0 to 1.50, and a TE.sub.01 .delta.-mode dielectric resonator in which using the dielectric ceramic.

Abstract: The invention provides a dielectric ceramic including as the main component a complex oxide formed of both Zr and Ti, at least one component selected from the group (A) consisting of {Mg, Co, Zn, Ni and Mn} and at least one component selected from the group (B) consisting of {Nb and Ta} and a TE.sub.01 .delta.-mode dielectric resonator including the dielectric ceramic, and also the invention provides a dielectric ceramic composition expressed by Formula (a):xZrO.sub.2 --yTiO.sub.2 --zA.sub.(1+w)/3 Nb.sub.(2-w)/3 O.sub.2(a)wherein A denotes at least one component selected from the group (A) consisting of {Mg, Co, Zn, Ni and Mn},x, y and z denote molar fractions ranging from 0.10 to 0.60, 0.20 to 0.60 and 0.01 to 0.70, respectively, and have the relation represented by Formula (.alpha.):x+y+z=1 (.alpha.)and w denotes a value of 0 to 1.50, and a TE.sub.01 .delta.-mode dielectric resonator in which using the dielectric ceramic.