A piezoelectric composition according to the present invention comprising: a carbon, and a main component composed of an alkali metal niobate based compound. The amount of carbon contained is 350 to 700 ppm by weight.

A piezoelectric vibration device includes an element mounting member provided with a recessed part, a vibration element held in the recessed part, and a lid closing the recessed part. The element mounting member includes an insulating base body including an inner bottom surface of the recessed part and an inner circumferential surface of the recessed part surrounding the inner bottom surface, a pair of signal terminals which are located on an outer surface of the base body and are electrically connected to the vibration element, a GND terminal which is located on the outer surface of the base body, and a shield film which is superposed on the inner circumferential surface of the recessed part and is electrically connected to the GND terminal.

A piezoelectric ceramic containing a perovskite-type compound containing at least Pb, Zr, Ti, Mn, and Nb, in which in an X-ray crystal structure analysis chart of the perovskite-type compound, there is no X-ray diffraction peak branching between a (101) plane of a main peak of a PZT tetra phase in a range of 2θ=30.5° to 31.5° and a (110) plane on which an X-ray diffraction peak is in a range of 2θ=30.8° to 31.8°, and a number of X-ray diffraction peaks based on the (101) plane and the (110) plane is one.

A piezoelectric composition including copper, germanium and a complex oxide represented by a compositional formula K.sub.mNbO.sub.3 and having a perovskite structure, in which m in the compositional formula satisfies 0.970≤m≤0.999, and with respect to 1 mol of the complex oxide, x mol % of copper in terms of a copper element and y mol % of germanium in terms of a germanium element are contained, wherein x satisfies 0.100≤x≤1.000 and y satisfies 0.000<y≤1.500.

A piezoelectric ceramic containing no lead as a constituent element is provided. Coefficient of variation C.V. of grain size of grains contained in the piezoelectric ceramic is 35% or less, and an image quality (IQ) image obtained by analyzing a cross section of the piezoelectric ceramic by an electron backscatter diffraction (EBSD) method shows that at least one of the grains has a grain size of 3 μm to 5 μm and an area ratio of a domain in said at least one of the grains is 85% or more.

A hybrid structure for a surface acoustic wave device comprises a working layer of piezoelectric material assembled with a support substrate having a lower coefficient of thermal expansion than that of the working layer, and an intermediate layer located between the working layer and the support substrate. The intermediate layer is a sintered composite layer formed from powders of at least a first material and a second material different from the first.

The piezoelectric composition is represented by the following Chemical Formula (1):
x[Bi.sub.mFeO.sub.3]-y[Ba.sub.mTiO.sub.3]-z[Bi.sub.mAlO.sub.3](1)
wherein 0.5x0.7995, 0.2y0.4, 0.0005z0.1, x+y+z=1, 0.96m1.04.

A piezoelectric composition comprises a plurality of crystal particles, wherein the piezoelectric composition includes bismuth, iron, barium, titanium, and oxygen; the crystal particle include a core and a shell having a contents of bismuth higher than that in the core and covering the core; and the total area of the cross sections of the cores exposed to the cross section of the piezoelectric composition is expressed as S.sub.CORE, the total area of the cross sections of the shells exposed to the cross section of the piezoelectric composition is expressed as S.sub.SHELL, and 100.Math.S.sub.CORE/(S.sub.CORE+S.sub.SHELL) is 50 to 90.

A ceramic dielectric including: a bulk dielectric including barium (Ba) and titanium (Ti); a ceramic nanosheet; and a composite dielectric of the bulk dielectric and the ceramic nanosheet.

A piezoelectric material includes a metal oxide containing at least Ba, Ca, Ti, Zr, and Mn, in which the piezoelectric material has a perovskite structure, in which: x, which represents a ratio of a content (mol) of Ca to A (mol) representing a total content of Ba and Ca, falls within a range of 0.10x0.18; y, which represents a ratio of a content (mol) of Zr to B (mol) representing a total content of Ti, Zr, and Mn, falls within a range of 0.055y0.085; and z, which represents a ratio of a content (mol) of Mn to the B (mol), falls within a range of 0.003z0.012, and in which the piezoelectric material satisfies a relationship of 0(|d.sub.31(20u)d.sub.31(20d)|)/|d.sub.31(20u)|0.08, and has a value of 130 pm/V or more for each of |d.sub.31(20u)| and |d.sub.31(20d)|.