Specifications

Denomination: 1 penny (1/240 pound)
Series: British pre-decimal bronze penny
Designer: Mary Gillick
Years of issue: 1953
Edge: Plain
Key mintages: No circulation issue. Specimen strikings only, from ~40,000 coronation sets (Britannia Coin Company).

No 1953 pennies were struck for circulation — the only ones in existence came from the Queen’s coronation specimen sets. If your “1953 penny” looks worn, it almost certainly escaped from a broken-up set; a true proof example is the collectible.

History

Elizabeth II acceded to the throne in 1952 on the death of George VI, but her first coins were not struck until her coronation year, 1953 — tradition held that the new reign’s coinage begin with the coronation (Britannia Coin Company).
No pennies were struck for circulation in 1953: with huge numbers of pennies already in circulation, the penny was the only denomination between the farthing and the half crown with no 1953 circulation issue (Wikipedia).
Instead, specimen sets were issued for the coronation, each containing a penny with Mary Gillick’s right-facing bust of the young Queen and the inscription ELIZABETH II DEI GRA BRITT OMN REGINA F D — the “BRITT OMN” (Queen of all the Britains) wording was unique to 1953 and dropped from all later issues as the Commonwealth changed (Wikipedia).
About 40,000 of these sets were issued by the Royal Mint in 1953, sold for only a slight advance on face value — so many were later broken open and the coins spent, which is why worn 1953 pennies turn up in circulation finds despite never being issued for it (Britannia Coin Company; Wikipedia).
A smaller number of rare 1953 VIP sets with a frosted finish were issued, possibly to dignitaries and Royal Mint staff; the exact number made is unclear (Britannia Coin Company).

What is it worth

Value lives entirely in the proof/specimen examples: a genuine 1953 penny in proof condition carries a collector premium well above face value, while the price is modest compared with truly rare British pennies because 40,000 sets were issued (Britannia Coin Company).
Worn examples found in change are genuine coronation-set coins that escaped into circulation — interesting, but worth little over face value in worn condition (Wikipedia).
Complete 1953 coronation sets in original cases trade as collectibles in their own right; auction estimates for cased sets run in the tens of pounds (Gildings, Dec 2024).
No verified public auction record for a single 1953 penny was located in the sources consulted for this entry — treat any confident price quote without a cited sale with skepticism.

What drives the premium

Value drivers: proof condition and original surfaces first — mirror fields and full mint red color command the premium; the VIP frosted-finish strikings are the true rarities of the issue (Britannia Coin Company).
The one-year-only BRITT OMN inscription makes the 1953 penny a distinct type that type collectors need, supporting demand beyond date collectors (Wikipedia).
Original packaging adds value: coins still in the intact 1953 set are worth more than the same coins loose (Gildings).

How to identify the valuable variety

There is no such thing as a 1953 circulation penny — every genuine 1953 penny is a specimen/proof striking from the coronation sets. A proof example shows mirror-like fields and sharp, squared rims; a worn, dull example is a set coin that was spent (Wikipedia; Britannia Coin Company).
Check the inscription: ELIZABETH II DEI GRA BRITT OMN REGINA F D. The BRITT OMN wording appears only on 1953 coinage — later Elizabeth II pennies read DEI GRATIA without it (Wikipedia).
The portrait is Mary Gillick’s uncrowned young head, facing right — the first coinage portrait of Elizabeth II (Wikipedia).
Beware altered dates: a 1953 penny cannot be “found in pocket change” as a circulation issue, but genuine spent proofs do circulate — wear alone doesn’t make it fake, it just makes it worth far less (Wikipedia).

Specifications

Composition: Bronze (standard pre-decimal penny alloy)
Weight: Not verified in consulted references
Diameter: Not verified in consulted references
Edge: Plain
Alignment: Not verified in consulted references
Designers: Obverse: Mary Gillick — uncrowned bust of Elizabeth II (Wikipedia); reverse: seated Britannia (no design change from prior reign’s bronze, per Wikipedia)
Mint: Royal Mint, London — specimen strikings only; no circulation issue (Wikipedia)

Collector notes

One 1954 penny is known — struck for die-testing and intended for melting but recovered from circulation — making 1953–1954 a fascinating two-year “what if” pocket in the penny series (Wikipedia).
If you buy a 1953 set, check all ten coins are present (halfcrown to farthing, sometimes plus the coronation crown) and look for the VIP frosted finish, which multiplies value (Britannia Coin Company).