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
Porcelain crab are "Petrolisthes quadratus", found in large numbers under rocks in the intertidal, and the red-and-white polka-dotted "Porcellana sayana", which lives commensally within the shells inhabited by large hermit crabs. In Hong Kong, "Petrolisthes japonicus" is common. , some 4723 extant species porcelain crab had been described, divided among these 30 genera: The fossil record of porcelain crabs includes species of "Pachycheles", "Pisidia", "Polyonyx", "Porcellana", and a further 6 genera known only from fossils: The earliest porcelain crab fossil is "Jurellana" from the Tithonian of central Europe. Porcelain crab Porcelain crabs are decapod crustaceans in the widespread family Porcellanidae, which superficially