SINKS ARE MADE FROM SAND AND GRAVEL New River Concrete Countertops and Sinks are made of sand and gravel from the New River, which runs through North Carolina, Virginia and West Virginia. The concrete mix reduces portland cement content by substituting fly ash and vitreous calcium aluminisilicate, which are reactive pozzolins and pre-consumer recycled materials. The sinks are stained with recycled iron oxides and sealed with a water-based, low-VOC sealer. (276) 579-3117 /