Embodiments of the present disclosure provide an interrogation device that is operable to apply one or more source signals to one or more coils surrounding a volume, where a material is disposed within the volume. Each of the one or more source signals may excite one of the one or more coils, and the behavior of each the one or more coils responsive to the exciting may be monitored. One or more parameters may be determined based on the behavior of each the one or more coils, and the one or more parameters may be utilized to generate a signature for the material within the volume. The signature may be compared to one or more signatures of known materials to identify the material within the volume.