A magnetic resonance contrast agent consisting of: a nonmagnetic medium; and a plurality of contrast structures of one type dispersed in said nonmagnetic medium, wherein said contrast structures are made from a magnetic material arranged in a type being either as a pair of disk-shaped magnetic components (102, 104) defining a fixed space therebetween, said pair of disk-shaped magnetic components being arranged substantially parallel to each other, or as a substantially cylindrical magnetic structure, a substantially spherical shell-formed magnetic structure or a substantially ellipsoidal shell-formed structure, each of which defining a hollow region therein, wherein, depending on the type, the fixed space or the hollow region has a spatially extended region contained within a near-field region of the contrast structures over which a total magnetic field is substantially homogenous and substantially different in magnitude from any applied background magnetic field, such that nuclear magnetic moments of a material when arranged within said spatially extended region precess at a characteristic Larmor frequency corresponding to said total magnetic field in the local region, such that the magnetic resonance contrast agent will emit a magnetic resonance signal at said characteristic Larmor frequency when the magnetic resonance contrast agent is irradiated with resonant RF electromagnetic radiation of said characteristic Larmor frequency. a nonmagnetic medium; and a plurality of contrast structures of one type dispersed in said nonmagnetic medium, wherein said contrast structures are made from a magnetic material arranged in a type being either as a pair of disk-shaped magnetic components (102, 104) defining a fixed space therebetween, said pair of disk-shaped magnetic components being arranged substantially parallel to each other, or as a substantially cylindrical magnetic structure, a substantially spherical shell-formed magnetic structure or a substantially ellipsoidal shell-formed structure, each of which defining a hollow region therein, wherein, depending on the type, the fixed space or the hollow region has a spatially extended region contained within a near-field region of the contrast structures over which a total magnetic field is substantially homogenous and substantially different in magnitude from any applied background magnetic field, such that nuclear magnetic moments of a material when arranged within said spatially extended region precess at a characteristic Larmor frequency corresponding to said total magnetic field in the local region, such that the magnetic resonance contrast agent will emit a magnetic resonance signal at said characteristic Larmor frequency when the magnetic resonance contrast agent is irradiated with resonant RF electromagnetic radiation of said characteristic Larmor frequency. as a pair of disk-shaped magnetic components (102, 104) defining a fixed space therebetween, said pair of disk-shaped magnetic components being arranged substantially parallel to each other, or as a substantially cylindrical magnetic structure, a substantially spherical shell-formed magnetic structure or a substantially ellipsoidal shell-formed structure, each of which defining a hollow region therein, wherein, depending on the type, the fixed space or the hollow region has a spatially extended region contained within a near-field region of the contrast structures over which a total magnetic field is substantially homogenous and substantially different in magnitude from any applied background magnetic field, such that nuclear magnetic moments of a material when arranged within said spatially extended region precess at a characteristic Larmor frequency corresponding to said total magnetic field in the local region, such that the magnetic resonance contrast agent will emit a magnetic resonance signal at said characteristic Larmor frequency when the magnetic resonance contrast agent is irradiated with resonant RF electromagnetic radiation of said characteristic Larmor frequency.