Royal worcester dating system
In 1775, George III granted Derby Porcelain the right to incorporate the crown into the Derby backstamp. William Duesbury fully acquired the famous Chelsea Works factory in 1770 and the Chelsea anchor mark and Derby ‘D’ were merged to form the Chelsea-Derby mark.A group of former employees set up a factory in King Street in Derby, and continued to use the moulds, patterns and trademarks of the original business, but not the name.
The resulting mark was often uneven and sometime arced.This took the form of a small graphic illustration below the main mark and later, from 1938, a Roman numeral.The V of 1904 can be confused with the Roman V of 1942 as can the X for 1901 and the Roman X for 1947.This tends to protect the use of these marks, and in general restricts them to use on pieces made in the UK.
This protects both collectors and the companies who registered the marks.
Their production is marked with one or the other of the several versions of the Wedgwood and Bentley mark.