A ferrite powder for bonded magnets having a high iHc value usable even in a low temperature environment, a method for producing the same, and a bonded magnet using the ferrite powder and having high iHc value which can be used even in a low temperature environment, wherein a specific surface area is 2.20 m.sup.2/g or more and less than 3.20 m.sup.2/g; a compression density is 3.30 g/cm.sup.3 or more and less than 3.60 g/cm.sup.3, and a compressed molding has a coercive force of 3250 Oe or more and less than 3800 Oe.

A ferrite powder for bonded magnets having a high iHc value usable even in a low temperature environment, a method for producing the same, and a bonded magnet using the ferrite powder and having high iHc value which can be used even in a low temperature environment, wherein a specific surface area is 2.20 m.sup.2/g or more and less than 3.20 m.sup.2/g; a compression density is 3.30 g/cm.sup.3 or more and less than 3.60 g/cm.sup.3, and a compressed molding has a coercive force of 3250 Oe or more and less than 3800 Oe.

Provided is a composite member including: an inorganic matrix part made from an inorganic substance that includes at least one of a metal oxide or a metal oxide hydroxide as a main component, contains substantially no single metal and alloy, and is a diamagnetic substance or a paramagnetic substance; and a ferromagnetic material part that is present inside the inorganic matrix part, directly bonds with the inorganic substance making up the inorganic matrix part, and is made from a ferromagnetic substance. In the inorganic matrix part, particles of the inorganic substance are continuously present, and the inorganic matrix part has a larger volume ratio than that of the ferromagnetic material part.

Provided is a composite member including: an inorganic matrix part made from an inorganic substance that includes at least one of a metal oxide or a metal oxide hydroxide as a main component, contains substantially no single metal and alloy, and is a diamagnetic substance or a paramagnetic substance; and a ferromagnetic material part that is present inside the inorganic matrix part, directly bonds with the inorganic substance making up the inorganic matrix part, and is made from a ferromagnetic substance. In the inorganic matrix part, particles of the inorganic substance are continuously present, and the inorganic matrix part has a larger volume ratio than that of the ferromagnetic material part.

Microspheres, populations of microspheres, and methods for forming microspheres are provided. One microsphere configured to exhibit fluorescent and magnetic properties includes a core microsphere and a magnetic material coupled to a surface of the core microsphere. About 50% or less of the surface of the core microsphere is covered by the magnetic material. The microsphere also includes a polymer layer surrounding the magnetic material and the core microsphere. One population of microspheres configured to exhibit fluorescent and magnetic properties includes two or more subsets of microspheres. The two or more subsets of microspheres are configured to exhibit different fluorescent and/or magnetic properties. Individual microspheres in the two or more subsets are configured as described above.