en2015-08-18 18:07 PM CESThttp://inspire.ec.europa.eu/codelist/CommodityCodeValue/pozzolan:1http://inspire.ec.europa.eu/codelist/CommodityCodeValue/pozzolanPozzolan is a siliceous or siliceous and aluminous material which will react chemically with calcium hydroxide to form compounds possessing cementitious properties (ASTM C618). The broad definition of a pozzolan imparts no bearing on the origin of the material, only on its capability of reacting with calcium hydroxide and water.... The general definition of a pozzolan embraces a large number of materials which vary widely in terms of origin, composition and properties. - http://en.wikipedia.org/wiki/Pozzolan