The composition of the purification elements  Black Berkey® used in Berkey® systems is an exclusive, patent-protected formulation based on the assembly of six different types of specific media, including very high quality activated carbon. Assembled in a very compact matrix containing millions of microscopic pores, they allow the creation of a "tortuous path" through which the water will pass but not the pollutants. Indeed, these channels are so fine that all undesirable elements are inevitably captured. Through absorption and adsorption, even submicron viruses are blocked, which other water filters cannot achieve without chemicals.

The activated carbon block is impregnated with an ion exchange resin. Activated carbon adsorbs or chemically binds to organic compounds, such as petroleum-based fuels and solvents, many pesticides and pharmaceuticals. Ion exchange resin removes many dissolved metals from water by exchanging toxic heavy metals (such as lead, mercury and cadmium) for lighter, essentially harmless metals (such as sodium, the main component of table salt). All this allows for a complete and extremely efficient filtration.

Furthermore, the manufacturer Berkey® New Millenium Concept Ltd. confirms that no graphene oxide is used in the composition of the elements.

More details can be found on the page dedicated to the operation of Berkey® water filters.