Published online by Cambridge University Press: 09 November 2011
Amongst the most striking objects to survive from the three decades preceding the Roman conquest of Britain are the magnificent series of gold coins of Cunobelin. They are numerous and display an exceptional range of styles, from the traditional through the barbaric to the severely classical. Enough remain to permit a thorough die study, from which some interesting conclusions for the period can be drawn.
1 For the distribution of Cunobelin's coins see Ordnance Survey Map of Southern Britain in the Iron Age (1962), Map 5. This is based on the information recorded in S. S. Frere, Problems of the Iron Age in Southern Britain (1961), 225–35. A convenient map is in R. P. Mack, The Coinage of Ancient Britain (2nd Edition, 1964), 64. The Biga series is apparently confined to Essex. The Linear series is only recorded in Kent in the post-conquest hoard from Borden. There is some reason to think that only the Classic series is found in Suffolk, e.g. in the hoard from Lakenheath. Otherwise there is no distinction between the distribution of the various series.
2 In Archaeologia xc (1944), 24, I presumed an order on partial evidence which can now be shown to be wrong.Google Scholar
3 For some investigations into the possible life of ancient dies see D. G. Sellwood, ‘Experiments in Greek Minting Technique’, Numismatic Chron., 1963, 226–30. Figures for ancient coinage necessarily depend on experiments, but for the Middle Ages it is fairly well established that one obverse die with two reverse dies could produce about 10,000 coins: see Grierson, P., ‘The volume of Anglo-Saxon coinage’, The Economic History Review, xx (1967), 153 f.CrossRefGoogle Scholar
4 I am informed by Mr. Stewart Lyon, to whom I am much indebted, that a reasonably accurate estimate can be made of the proportion of an original coinage which was struck from the dies of which a record survives. The formula is that the proportion of surviving coins which are not unique representatives of the dies from which they were struck is a good estimate of the proportion of the original coinage which was struck from the recorded dies. The error is not likely to exceed 100/N √3ni%, where ni is the number of unique dies out of the total of N surviving coins of the type. It must be presumed that the sample of the coinage is a random one. (The formula was first devised in a biological context, see Good, I. J., ‘The population frequencies of species and the estimation of population parameters’, Biometrika xl (1936), 237–64)Google Scholar. Applied to gold coins of Cunobelin, stater obverses would indicate that 76% of the coinage was struck from surviving dies, stater reverses 75%±6% in either case. The corresponding figures for quarterstaters are 72%±7% and 58%±4%. The method is described by Mr. Lyon in Mossop, H. R., The Lincoln Mint (Newcastle upon Tyne, 1970), 16–19.Google Scholar
5 Suetonius, Divus Iulius, 25, with Eutropius, vi, 17; for Britain cf. Caesar, BG, v, 22, 4, where no figure is given.
6 No. 66 was found at Ambresbury Banks (TL 438004), which is probably the find-spot of the rest.