What advantage does Ilmenite have over garnet as a high density filter material?
Garnet is the name of an entire group of crystalline materials exhibiting the same structure, but with different elements occupying different positions in the crystal. Each of these garnets exhibits a different specific gravity. The most common variety is known as Almandine which has a specific gravity of approximately 4.2 in pure forms. Although still referred to as ilmenite (FeTiO3), the non-garnet high-density material in common use today is really a mixture of magnetite (Fe2O3) and hematite (Fe2O4) that have a specific gravity normally in excess of 5.1. High-density materials are normally employed because of their relative densities, either as “hold down” gravel, or as high-density media. All things being equal, the higher the density, the more desirable the material. However, sometimes other considerations such as availability, transportation cost, or even chemical properties may influence the optimal choice.
