File:A scattered horad of four silver and two gold ingots. Treasure case 2009 T181. (FindID 251844).jpg

1. Gold 'finger' ingot. Rectangular shape, flat on the underside, truncated planoconvex in profile; the terminal ends are rounded and the sides bevelled from the flat upper surface. There are a series of visible hammer marks in a number of places on the surface, but no stamps or inscriptions.
L.: 70.4mm W.: 17.2mm thickness: 7.1mm Wt.: 113.9g AV content: c. 93-5% AR: c 4-6%

2. Gold 'finger' ingot. Sub-rectangular, flat on both sides, slightly rounded ends and bevelled edges. There are a number of visible hammer marks, minor scratches and pitting, but no stamps or inscriptions.
L.: 61.7mm W.: 15.3mm T.: 4.8mm Wt.: 66.8g AV: c. 87-90% AR: c. 9-12%

3. Silver 'cake' ingot, a flat ovoid shape, slightly convex on the underside. The flat upperside surface is pitted and irregular; the convex lower surface has distinctive 'rice grain' indentations covering most of the surface, suggesting contact perhaps with an organic material onto which the metal had been poured. There are further pits and small surface protrusions.
L.: 82.9mm W.: 66.5mm T.: 9.5mm Wt.: 320.3g AR: c. 97%

4. Silver 'cake' ingot. Roughly ovoid in shape, the upper surface flat but pitted and scratched. The convex underside is extremely irregular, giving the appearance that the metal had been poured into a rough hollow in a ground surface. The edge is also irregular with a distinctive knob shaped projection.
L.: 73.6mm W.: 65.7mm T.: 12.2mm (widest point) Wt.: 239.2g AR: c. 96%

5. Silver 'cake' ingot. Sub-ovoid in shape, flat on the upperside, gently convex on the lowerside. The upperside surface is flat with some sub-circular pitting. The underside has similar 'rice grain' indentations to no. 3, suggesting a similar surface into which the metal had been poured.
L.: 69.7mm W.: 55.5mm T.: 10.5mm Wt.: 229.2g AR: c. 97%

6. Silver 'cake' ingot. Sub-circular ingot, planoconvex in profile; the upperside is flat with some irregular pitting. The underside is rough and pitted with some particularly deep pits, implying an irregular surface into which the metal had been poured (similar to no. 4).
L.: 63.7mm W.: 56.7mm T.: 10.8mm Wt.: 176.9g AR: c. 98%

7. Silver 'cake' ingot. Sub-ovoid in shape, planoconvex in profile; the upperside is flat with some irregular pitting. The lower convex surface is pitted and has a few 'rice grain' indentations (as nos. 3 & 5) and one particularly deep and wide indentation.
L.: 63.8mm W.: 49.2mm T.: 10.9mm Wt.: 154.2g AR: c. 93%

8. Silver 'cake' ingot. Sub-rectangular in shape, planoconvex in profile. The flat upperside has some irregular pitting. The lowerside is slightly convex, with some 'rice grain' indentations and one deep pit which runs deep into the ingot's interior. One edge appears to have been snipped or chopped with a straight blade.
L.: 51.1mm W.: 36.0mm T.: 9.3mm Wt.: 95.8g AR: 98%

9. Silver 'cake' ingot. Sub rectangular in shape, planoconvex in profile. The flat upperside with one distinctive protusion. The lowerside is pitted and irregular, roughly convex, with no visible signs of the 'rice grain' appearance of others in the group, suggesting a different pouring surface.
L.: 58.6mm W.: 37.0mm T.: 9.1mm Wt.: 91.5g AR: 98%

Discussion and dating: this group of ingots cannot be easily paralleled. The form of the gold ingots is quite distinctive but provides no diagnostic indicators for the date of manufacture, and the silver ingots are entirely undiagnostic. Initially, an Iron Age date was considered, since the silver ingots bear comparison to a small number in the Snettisham hoard (Stead 1991) which date to the late pre-Roman Iron Age. But the ingots have less in common with examples from the East Leicestershire hoard (TAR 2000, no. 236) and ingots associated with Iron Age coins from Shalfleet on the Isle of Wight (2009 T460) and South Wight (2004 T131; see TAR 2004, no. 421; Joy & Leins pers. comm.). In addition, metal analysis of Iron Age ingots has generally produced much lower silver and higher gold values than the ones in consideration here. For all these reasons, an Iron Age date does not seem likely. The ingots do not bear comparison either with examples from the early or late medieval periods (Marzinzik & Ager pers. comm.). A modern date can also be discounted, because of the presence of the gold, which you would expect to have been extracted (La Niece, pers. comm.).

A Roman date is however possible. The metallurgical results, producing very high silver values with relatively low gold content bears comparison with analyses of Roman silver plate, which typically produce very high silver values (e.g. analyses of silver spoons in the Thetford treasure, see Cowell et al. in Johns & Potter 1983, pps. 56-9). There are also some parallels with the shape of ingots found in association with dated Roman material: these include a stamped 'cake' ingot from Nijmegen (Wiegels 2003, cat. 56, plate IX, 6a&b) and a silver 'finger' ingot from Niedersachsen (ibid. cat. 60, plate X, 4a&b). The case for a Roman date would have been strengthened if the weights bore comparison with the Roman pound (c. 324g) but only one of the ingots (no. 3) can be considered close to a full pound and the others do not form obvious pound fractions.

References:

Johns, C.M. & Potter, T. 1983. The Thetford treasure. Roman jewellery and silver. London.
Wiegels, R. 2003. Silberbarren der römischen Kaiserzeit. Katalog und Versuch einer Deutung. Leidorf.
TAR = Treasure Annual Report

Note: these items are made substantially of gold silver and are more than 300 years old, and thus qualify as treasure as stipulated in the Treasure Act 1996.

Richard Hobbs BSc PhD FSA
Curator, Romano-British Collections, Prehistory & Europe, The British Museum

22nd July 2010