The Marks That Date an Object Exactly

Most evidence gives a rough period. Four marking systems give a year, and one gives a day.

The British registry diamond, 1842 to 1883

A diamond-shaped mark with letters and numbers in the corners, found on ceramics, glass, metalwork and textiles.

It records the registration of a design with the British Patent Office, and the codes give the exact day, month and year. Two different arrangements were used, one from 1842 to 1867 and another from 1868 to 1883, and published tables decode both.

After 1884 the system changed to a simple sequential Rd No — a registered design number — which also dates closely, since the number issued at the start of each year is documented.

This is the single most precise dating mark on ordinary domestic objects.

British silver hallmarks

The most informative marking system anywhere, and it has legal force behind it.

A full set gives four or five marks:

• The standard mark — a lion passant for sterling
• The town mark — which assay office tested it
• The date letter — a letter in a specific typeface within a specific shield shape
• The maker's mark — initials in a shaped punch
• Sometimes a duty mark — a sovereign's head, indicating 1784 to 1890

The date letter cycles through the alphabet and the combination of letter, font and shield shape is unique to one office in one year. Reference tables give the exact year.

American silver gives far less. "Sterling" or "925" indicates roughly 1860 onward; "coin" indicates earlier. There was no compulsory assay system.

Worth knowing: EPNS, EP and A1 mean electroplate — plated base metal, not silver, and worth a small fraction. More detail on silver hallmarks.

Patent numbers and dates

An object marked "Pat. Nov. 12 1889" or with a patent number can be looked up directly in patent office records, and the grant year is exact.

Two cautions:

• A patent date is when the design was granted, not when the object was made. Manufacturers kept stamping the same date for decades.
• "Patent applied for" or "Pat. Pend." indicates the gap between filing and grant, which is a narrow window and therefore useful.

So a patent date gives a hard floor — the object cannot predate it — and a soft ceiling.

Country of origin

Dull and extremely useful.

• A country name alone — "England", "Germany", "Nippon" — indicates 1891 or later, when the US McKinley Tariff Act began requiring imports to be marked.
• "Made in ..." generally indicates 1914 or later, when the requirement was tightened.
• "Nippon" specifically indicates 1891 to 1921, after which "Japan" was required.
• "Occupied Japan" dates exactly to 1945 to 1952.
• "West Germany" dates to 1949 to 1990. "US Zone Germany" to 1945 to 1949.

None of these tells you an object is old. All of them tell you it is not older than a certain date, which is frequently what you need.

Marks that mislead

"Limited" or "Ltd" in a company name indicates 1861 or later in Britain — useful, and often overlooked.

Crossed swords, crowns and shields are imitated constantly. Meissen's crossed swords are among the most copied marks in existence, and a crossed-swords mark on its own means very little.

Impressed date codes in ceramics are often a batch or mold number rather than a year.

Marks that do not exist in any reference are fakes. The reference tables are freely available and a mark that corresponds to no recorded office, maker or year is conclusive evidence in the wrong direction.

The order to work in

Marks first, when there are any, because they are the fastest evidence available. Then construction — the five checks — which is what you fall back on when there are no marks at all, which is most of the time.