Meissen porcelain further precaution, very few workers knew the special secret ("arcanum") of how to make porcelain, and then perhaps only part of the process. Thus, for a few years, Meissen retained its monopoly on the production of hard-paste porcelain in Europe. By 1717, however, a competing production was set up at Vienna, as Samuel Stöltzel sold the secret recipe, which involved the use of kaolin, also known as china clay. By 1760 about thirty porcelain manufacturers were operating in Europe, most of them, however, producing frit based soft-paste porcelain. In order to identify the original Meissen products, Meissen developed markings that
Van Tilburg Collection (1465-1487), Hongzhi (1488-1505), Zhengde (1506-1521), Jiajing (1522-1566) and Wanli (1573-1619) wares are found in the Collection. Noteworthy Kangxi (1662-1722) and Qianlong (1736-1795) pieces are the large blue-and-white porcelain chargers, the underglaze red pots and blue-and-white ritual stand with two side vases. There are numerous polychrome Kangxi 'Famille verte' and Qianlong 'Famille rose' plates in the collection. The collection holds a pair of 'Famille noire' pots which belonged to the Kangxi Emperor. There are also a number of Imperial Japanese pieces in the collection, among them a blue-and-white Arita gendi with Arabian ormulo mouldings, an early 19th-century blue-and-white Arita charger decorated