Unique abrasive materials that are in situ generated compositions of precipitated silicas and silica gels are provided. Such compositions exhibit different beneficial, particularly simultaneously high pellicle film cleaning properties and moderate dentin abrasion levels. Such a result thus accords the user a dentifrice that effectively cleans tooth surfaces without detrimentally abrading such surfaces. Furthermore, the produced abrasive materials also exhibit very high and desirable brightness properties that permit easy incorporation and utilization within dentifrices for aesthetic purposes. Encompassed within this invention is a unique method for making such gel/precipitated silica composite materials for such a purpose, particularly under high shear conditions, as well as the different materials within the structure ranges described above and dentifrices comprising such.