The evolution of papermaking from 12th century, in Europe, was characterized by continuous changes of fibrous and non-fibrous materials as cellulose, wood
pulp, sizing agents, fillers and coatings. Over the years different fillers surface coatings or chemical additives have been added during the paper making process to
improve the quality of the product. Other changes in the manufacturing processes have occurred for economic or environmental reasons. These innovations and
modifications can establish the earliest date or period a particular sheet of paper was manufactured.