Abstract: A ceramic composition which includes Pb(Mg.sub.1/3 Nb.sub.2/3)O.sub.3 or the oxide precursors thereof, in admixture with barium copper oxide of the formula BaCuO.sub.2 as a sinter aid therefor. The compositions do not contain any free lead oxide and have high dielectric constants, e.g. above 8000, and low loss factors, e.g. below 3%.

Abstract: A low temperature fired ceramic dielectric composition in which the dielectric constant does not vary from its base value of over 2400 by more than 15 percent over a wide temperature range. A base ceramic preparation (a) and a ceramic flux (b), each consisting essentially of metal oxides or precursors thereof to provide in oxide form (a) 98.0 to 99 weight percent barium titanate, from about 0.97 to about 1.54 weight percent niobium pentoxide and from about 0.19 to about 0.32 weight percent cobalt oxide; (b) from about 16 to about 60 weight percent bismuth titanate, about 8 to about 52 weight percent lead titanate, about 18 to about 35 weight percent zinc oxide and about 5 to about 11 weight percent boron oxide. Manganese dioxide or precursor thereof in amount of from about 0 to 0.

Abstract: A low fired, temperature compensating dielectric composition is disclosed. The invention dielectric is formed of a base ceramic and a frit material. The base ceramic includes magnesium oxide, titanium oxide, calcium oxide, alumina, silica and at least one oxide of a rare element from the group of niobium, neodymium, tantalum, lanthanum, yttrium and praseodymium. The preferred oxides are those of niobium alone or with neodymium.