Most non-polar dielectric materials would provide an intrinsic dielectric constant of not more than 100.

except ferroelectric which show a high dielectric constant at the TC the transition temperature.  

Materials like CaCu3Ti4O12 do exhibit very high dielectric constants in the low frequency range, but such measurements are beset with measurement problems relating to extrinsic effects arising from surface layer effects and interfacial capacitance effects, and therefore project erroneous values of high dielectric constant in 10's of thousands which does not represent the intrinsic value dielectric consant, and is in fact very low.

K. Sreenivas

Cf. (e.g.): David R. Lide (Ed.), "CRC Handbook of Chemistry and Physics", 85th ed., CRC Press, 2004, pp. 12-48 to 12-56; or other eds.

Thank you all for the valuable information