The only surviving example of a coin from the Horndon mint was among the hoard of coins found in the 18th century in a basement near St Mary Hill church, in the ward of Billingsgate, London, England.  The coin is described as being of the sovereign/martlet type, with the head of the sovereign and a martlet mint mark; it was minted between 1056 and 1059. It bears the inscription Dudinc on Hornidune on the reverse. Hornidune is the earliest recorded form of Horndon, which appears in Domesday as Horniduna.
From the reign of King Edgar onwards many mints were established to meet the need for new coins when the older ones were withdrawn. This happened regularly, partly to counteract inflation, but also to provide income to the king.
The existence of a mint at Horndon is described by Frank Stenton as signifying "a claim to be regarded as a borough" and Horndon was noted as an Anglo-Saxon town by Aston and Bond based on possession of a mint. A number of small mints were established during the reign of Edward the Confessor, but the choice of Horndon which was an "undistinguished village" is not obvious. Sydney suggests that the solution may be that the manor of Horndon was under the influence of Robert FitzWimarc and his son Swein of Essex, a powerful and ambitious local family.
- Metcalf, DM; Lean, W (1993). "The battle of Maldon and the Minting of Crux Pennies in Essex". In Cooper, Janet. The Battle of Maldon: Fiction and Fact. Hambledon Press. p. 223.
- Metcalf, David Michael (1998). An atlas of Anglo-Saxon and Norman coin finds, c.973-1086. Royal Numismatic Society. p. 222.
- Sydney, John (1980). "The Horndon Mint". Panorama, the Journal of the Thurrock Local History Society 24: 52–57. reprinted from Coins and Medals Monthly. July 1980. Missing or empty
- Reaney, PH (1935). The Place-names of Essex. Cambridge University Press. p. 157.
- Anglo-Saxon coinage
- Stenton, Frank (2001). Anglo-Saxon England (3rd ed.). Oxford University Press. p. 536.
- Aston, Mick; Bond, James (2000). The Landscape of Towns. Sutton Publishing. p. 59.