To provide an iron hydroxide-based improved granule which has high ability to combine with a contamination in a liquid or a gas, high mechanical stability, high fluidity and low moisture content and achieves sufficient mechanical stability without using another organic or inorganic binder.

This stable adsorber granule exhibits <600 FNU turbidity when measured by the turbidimetric test defined in the specifications and is composed substantially of iron oxide and/or iron oxyhydroxide.