The diamond-shaped English Registry mark, was used by the English patent office since 1842 to identify pieces of English pottery, porcelain, and other products. It is easy to tell when the ceramic was made. The mark has the Roman numerals "IV" at the top of the mark if it is for a ceramic. Between 1842 and 1883, the diamond-shaped mark was used. Marks registered from 1842 to 1867 have a letter at the top of the diamond. Marks registered from 1867 to 1883 have a number instead of a letter at the top of the diamond. After 1883, the diamond shape was discontinued and "Rd. No.," followed by the number assigned to the ceramic, was used. Tables listed here tell how to decode the mark to learn the type of material, month, maker, and year of manufacture.
To obtain more detailed information, contact one of the following offices or visit their websites:
The National Archives
Richmond Surrey IW9 4DU, UK
Intellectual Property Office
South Wales NP10 8QQ, UK
Both offices will research designs for a fee. Information is available on their websites.
Here are some notes to help date any piece that bears an English registry mark.
A diamond-shaped registry mark was used between 1842 and 1883. The information within the diamond changed after 1867.
Mark "A" represents the mark used between 1842 and 1867; mark "B" represents the mark between 1868 and 1883. After 1884, the diamond-shaped marks were replaced by the letters Rd. No. (for registered number)—and numbers indicating the year the piece was registered (see Mark "C).
In Mark "A," the various letters and numbers indicate the following: the large "Rd" means "registered"; the Roman numeral in the circle at the top of the mark represents the type of material used to make a piece (see Table 1); the Roman numeral in the top inside section of the diamond represents the year the piece was registered (see Table 3); the Arabic numeral on the right-hand section represents the day of the month the piece was registered; the Arabic numeral in the section at the bottom represents the parcel number, which is a code indicating the person or company that registered the piece; and the letter in the left-hand section represents the month the piece was registered (see Table 2). In other words, Mark "A" appeared on a piece of ceramics registered on June 2, 1850.
In Mark "B," the various letters and numbers reflect the following: the large "Rd" means "registered"; the Roman numeral in the circle at the top of the mark represents the type of material from which the piece was made (see Table 1); the Arabic numeral in the top inside section of the diamond represents the day of the month; the letter at the right-hand section represents the year the piece was registered (see Table 4); the letter in the bottom segment represents the month the piece was registered (see Table 2); and the Arabic numeral at the left-hand side represents the parcel number. In other words, this mark appeared on a piece of ceramics registered on July 7, 1873.
After 1883, the diamond marks were discontinued and a simpler marking system, consisting of the letters "Rd No" followed by a number, was instituted. This mark appears on decorative art (china, glass, metal, or wood) manufactured in England since 1884.
Table 5: Design Registry Numbers—1884-1981lists the English registry numbers by year. (For example, if a piece is marked with the number Rd. No. 821265, it was registered sometime in 1937.)
Based on information supplied by the United Kingdom's Intellectual Property Office.
* Textile designs had a separate Number sequence until 2001; this number was probably a textile design.
** 4-million sequence started in Oct. 2006 following new legislation.