Many ot the backstamps listed here are detailed in Geoffrey 'A Goddens Encyclopaedia of British Pottery and Porcelain Marks' and 'Encyclopaedia of British Porcelain Manufacturers' where that author gives an indication of when new styles were introduced.
These estimates are thought to have been based on information gathered from the Pottery Gazette Diary.
By 1989 the name and patterns had been absorbed into Royal Albert and by 1992 the Paragon name was discontinued.
Irving was a very astute businessman making the best of every opportunity afforded him.
He introduced modern methods of publicity such as window display competitions for retailers and he organised events attended by celebrities of the day.
Strict regulations govern the warrant, which allows the grantee or his company to use the legend 'By Appointment' and display the relevant Royal Coat of Arms on products.
Towards the end of the 20's Paragon had started labelling some of their better quality china 'Royal' Paragon.
Irving subsequently joined his father-in-law as a partner in the Star China Company when Illingworth retired in 1910.