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
Coalport porcelain keep up the pace of production. The technique was widely adopted by other manufactories during the 19th century. At The Great Exhibition (London 1851) an elaborate Coalport table service with deep borders of mazarin blue was shown; it had been commissioned by Queen Victoria as a gift to Tsar Nicholas I of Russia. The Coalport porcelain manufactory, the first porcelain factory in the Ironbridge Gorge, England, was founded by the practical and enterprising John Rose in 1795. Financial support was provided by Edward Blakeway (1720-1811). John Rose had probably trained at the Caughley porcelain manufactory, less than a mile away