The polycrystalline compounds with chemical formula (CSBFLO) were synthesized via standard ceramic method. The chemical phase analysis was carried out by X-ray powder diffraction (XRD) method, which confirmed the formation of the magnetoplumbite phase belonging to ferrite structure. The frequency dependence of AC conductivity and dielectric constant was studied in the frequency range of 10？Hz to 2？MHz. The experimental results revealed that AC conductivity increases with increasing frequency, which is in agreement with Koop’s phenomenological theory. However, variation in dielectric constant required explanation in light of dielectric polarization. Magnetic characterization included studies of parameters such as Ms, Mr, Hc, and Tc, and results were explained via magnetic dilution and canting spin structure. 1. Introduction M-hexaferrite is a hard ferrimagnetic material possessing magnetoplumbite phase of hexagonal structure which is widely used in various industrial applications. Along with M-hexaferrites, various other members like W, Z, Y, X, and U belong to this family and they can be distinguished as per their stoichiometry. However, M-hexaferrites have gained more attention because of their special characteristic of being magnetoplumbite in nature which leads to greater structural stability compared to other members. The general chemical formula by which M-hexaferrites are represented is MeFe12O19 where Me is the divalent alkaline metal cations and can be replaced by a suitable cation or their combinations. Among various hexaferrites, M-hexaferrite is preferred as permanent magnetic material due to its cost effectiveness, reasonable magnetic performances, and wide availability of raw materials needed for synthesis [1]. It finds numerous applications in diverse fields like high-density magnetic recording, microwave absorption devices, high power transmitters, high permeability ferrite components for digital switching equipment for the telecom requirement, high frequency microwave ferrites for VHF/UHF communication sets, defense radar requirement, and transmitter and receiver application in railway projects and can be used as building blocks for hexaferrite isolators [2–4]. The ferrimagnetic oxides with hexagonal crystal structure were first synthesized at the Philips laboratory in 1950 and were called hexagonal ferrites in order to distinguish them from the ferrimagnetic oxides with Spinel and Garnet structure [5]. The basic crystallographic and magnetic properties of the main hexagonal ferrites have been reviewed by Smit and Wijn [6]. The
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