Anthracite is a filter media derived from coal content, is shinier in color and functions to remove turbidity in water by filtering sediments / other solid particles. Anthracite has a lighter specific gravity than silica sand so that anthracite can be used as a substitute for silica sand in the filtration process or can also be used together with silica sand in multi-media filters. Anthracite can transport turbidity in the outer cavities and lift more dirt because Anthracite has larger cavities and can filter from top to bottom