George Jones (and Sons (Ltd.))
Trent Pottery Stoke, Stoke on Trent, North Staffordshire, Great Britain
Hersteller / Manufacturer
George Jones worked for Minton prior setting up his own factory, the Trent Pottery in 1861, which was situated directly behind the Minton factory. He was not a popular character with Minton as his very similar wares were in direct competition. As well as white, blue and white, and transfer-printed earthenware made for domestic use, he manufactured Majolica and Palissyware from circa 1867, adding porcelain in 1872. In 1873 the company became George Jones & Sons. George Jones died in 1893. By 1896 George Jones and Sons had became a Limited company. In 1907 the pottery was renamed Crescent Pottery, following the design of the later marks. Cauldon Pottery's production was moved to the Crescent Pottery in 1920, followed by Coalport's in 1924. However George Jones & Sons Ltd. ceased trading in 1951. Coalport China was moved from the Crescent Works to the factory of Samuel Redford, High Street, Fenton in 1955. The business of Cauldon Potteries was acquired by Pountney & Co. Ltd. of Bristol and manufacture of pottery at the Crescent Potteries ceased finally in 1962.
The markings added: "& Sons" in 1873; "England" from 1891; and "Crescent China" on some marks from 1893
References: The Potteries The Potteries 2 The Potteries 3 Millers Antiques Etruscanmajolica
The design for this stein was registered on the the 23rd December, 1871, and made within a year or two afterwards. 
The monogram only (i.e. without the crescent) was used circa 1861-72/3 when the company was just George Jones. 
The Roman numeral at the top of the diamond indicated the 'class' or type of material used - for example III was for glass ware and IV was for clay ware. The Rd stands for registered design. The top number is the day, the right hand letter is the year and the bottom letter the the month. The left hand number is the "bundle". Therefore this design registration mark on the featured stein translates as 23rd December 1871. 
The design for this stein was registered on the the 23rd December, 1871, and made within a year or two afterwards. 