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g

H FY SRFR HR

M. Ponng (Instute of Ahaology)

owds he end of summer 1990 durng he course of roadwors a

Galle Lane Fenn Saford Roman Magovnum jus souh of MlonKenes a local meal deecors' dscoved wha aeared o be he rawmaerals for he roducon of unoffcal Roman cons. he fnd comrsedhree ceramc vessels conanng hree gus of maeral and wo ron des forsrng he cons.

he dscove of such maeral alhough no que unque s ceranlve rare and nde hese e e frs n des found n Bran Con blsand elles have occued n assocaon wh suc unocal cons suh ashose n he Srobrough hoard Mangl and Dolb 198 and he hod omNorh Legh Vlla unublshed recenl nvesgaed a he Brsh Museum

Research Laboraores. However no suc cons were found n assocaonwh he Fenn Saford maeral. Consequel he onl relable avenue fordang la wh he denfcaon of he ceramc conaners alhough he szeand wegh of he blans suggesed a lae hrd cur dae.

he dencaon of he oer was caed ou b P Me of heMlon Kenes Archaeologcal Un. Unforunael he vessels roved raherunusual alhough boh fo and fabrc fall whn a wde range of daes. Meconcludes ha he vessels are oor maons of he BBl mnaure coong

o and goes on o sa ha he vessels e no eas o dae. Ceranl a daeof lae second o fourh cenur AD would cover all ossbles bu s raheroo generous. However he use of wld arcs as decoraon combned wh heslendeess of e vessels ma pers ndcae a dae n he lae rd or elfouh cenr AD. Me 1990unublshed oer reorhs of course agrees wh he dae suggesed b he sze and wegh of hebls and reblans and as shall be demonsraed laer s n agreemen whhe nerreaon of he analses.

Whn each of he hree vessels was a dsnc grou of maeral. Oevessel conaned 35 blans anoher 6 reblas arl hammered flsand he as vessel conaned some 150 cu lenghs of cas coerallo rod as

well as a small numb of wase offcus and swaMercal analses of he blans ad re-blas sugges a degree ofconol had been exesed ov he sze and wegh of he ans see fg.1. heaverage wegh of .7gm s n close agreemen wh wha one would exec forocal lae rd cenur base anninianii erhas beer called radaes ass he range of flan szes 1lmm.

he grou of elles are less well defned szes rangng om o 5mmn lengh and weghng hng om 0. o 085gm However he majorare around 3mm n lengh Examnaon of hese eces showed ha a numberwere suerng he eecs of ng - whee aed gasses and rad coolg of

he meal cause he desred sold rod o become a hollow e. hs maaccoun for he lge varaon n weghs. he dameer of he rod om whchhe elles were cu seems farl consan eeng o or 5mm suggesnga he dameer of he elles was conolled.

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to peentIOr----------------8 ............. .....................'-..._ .

6 -.....

..-. . ..... . .. ...... .......4 .

:---- --1- . . - . .. . . .. . -i ----- 6

fan wight (gm)

Fig.

he os that ths materal was tee to roue were oes of the

ofall roue raate or atoaus stgushe b the serown wo b the emeror hese os were roue massve quattesurng the ero AD 74-86 Reee 987 0 a are osequetl verommo as ste s a hoars Ma questos rema to be aswereabout the seres However the overall osesus of oo s that the weressue orer to me u or shortages oal ssues from e otetalmts Reee 987 0 B whom rom where the were ssue remasotroversal

Oe of the most ofusg asets of these os s the great varet ofqualt a sze that aear to exst at the same tme Some oes are er

well-roue a ol be stgushe b the trae ee whereas others roue o suh small las a are of suh veaul womash thate oul ever have bee mstae or ofal ssues Furthermore althoughman es we ue om well ut-es ma b o meas aemtgto be exat oes o ther rototes It seems therefore that there was otet to eeve volve the routo of ese oes a ths must

resuose at least some egree < oal satoGeorge Boo hs aer o Couterfet os Roma Brta' s of

the oo that the la o exat oes was ue to the arelessess wthwhh the habtats of the Roma Emre were at to regar the etals other oage Boo 9884 a that the oers sole oe was roug as ma os as ossble out of whatever metal he oul la therhas o he aaret ele sze o the oes over tme s see asevee of ths alough t s reogze that both large oes a smalloes rulate together alogse the gular os Boo 9889

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The initial assumpon for the Fny Saford maerial, as put forwd nboth the Independent newspaper (26/11/90) and Current Archaeologymagazine (1991: 122 [XI]271), was hat each group repesents a single stagein the roducion pocess for these 'Barbarous radiates'. The pelles beingmelted down o produce the pre-blanks' which were hen hammered out to

poduce he finished blanks. Analysis of a sample om each group has lea meo quesion this assumption, and also to question Boons inimalist approacho the sees in genel

The meical analysis above has shown that the weighs of both theblanks and 'preblanks' were quie tighly contlled; the average weightcoesponding to the weights of the regular coins. Aomic AbsorptionSpecscopy was en used to investigate he mateia further by looking ate composiion of the aoy used for each group.

Forfive sales om the Fenny Stratfo hoard wee each sampled forAAS The echniue employed is similar to hat developed by ELSzonntagh(1981) d nvolves he use of small diameter HSS twist dills (usually 06mm)o penetrate the blank at the cylindrical surface This technique inflictsmiimum visible dage whist at e same time sampling the enre crosssecon of the blank

In order to obtain as representaive a sample as possible, an average offour drillings were made into he blank, each peneaing to the cene Thedrillings were spaced euidistantly around the edge of the blank, usually inquadrants, alhough this was not always pracicable Approximately the firstmillimetre of drillings discarded in order o limit he effecs of surface

enrichmenUdepletion and contaminaion by coosion products. The drilingsexaced thereafer were carefully collected on analytical weighing paperswhich wee changed afer each sample Furhermoe, each specimen was held,durig drilling, in a boxwood jewellers ngvice, which was cafully busheddow after each sampling The drills themselves were used for mo than onesamle, the being no danger of conamation om this souce (Hughes et al197622) The resultant drillings from each blank or pellet were collecedogeher and amalgamaed hus creaing a homogeneous sample colleced from anumber of reasonably equidistant areas hroughout he specimen

After each specimen had been sampled, the holes were then plugged

using a twopart epoxyputty, coloured wih appropriate mineral dyes. By hs process the samplig damage was rendered amost completely invisible to henaked eye.

Aoic Absotion Specoscopy equies hat the sample to be analysedis in solution. Thus e 20mg or so of dillings colleced were digesed in 2 of Aqua Regia (a mixture of hydrochloric and niic acids) and the resultantiquids then made up to a sandd volume wih deionised waer. The analysish looked for telve elemen which had been decided upon by e resuls ofearlier work boh by the author and om he literatue. These were copper(Cu), tin (Sn), zinc (Zn), lead (Pb), silver (Ag), anmony (Sb), arsenic (As),

gold (Au), chomium (Cr), cobalt (Co), iron (Fe) and nicke (Ni) However, hegold and chmium proved o be consiseny below the decion limits of thensument and so we le out of the fna anaysis

Multivariate saisical mehods were hen used o examine the resulantdaa. It was mmediaely apparent hat two vey diferent groups of maeia are

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represented he. hese coespond dicy the bls and p-blas on onehand and the pelle on e other. The blas distinguished by a significantzinc content and the pelets y an unusually high tin content (Fig.2).

5

I

5

2

25

3

5

2

4

Sample No:

Logarythmic scae

Fi2 Plot o relative ZIncBlanks ae sample Nos534

(et) and TIn (riht contents

Pellets are sample Nos.3539

Consequenty it was decided o separate e two gups and eat them asseparate data sets. Because the techniques be employed assume that the dataare normally disibute, and to stabilize their variability, the data were logansformed. Where values deteced were below the detection limits of heequipment a value of half the detection limit was ascribed thus avoiding

probles wih zero values during e ansformation.Furthemore, it was felt ppriate remove all copper values om he

alysis in order render he data no longer ly 'composition By doingthis Aitchisons 1989) objections using standard multivaiate staisticalechniques on compositional da avoided.

Wards method cluster analysis was initially applied together wih principle component analysis of the covaiance maix. The combination ofthese two techniques hinted at possibilities for frthe subgoupings withinhe main maeial gups, although none were vey cle cu

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0

ig

I wa hefore dided, on he bai of he archaeomeallurgy, o diidehe daa ino hoe componen which were mo likely o hae been conolledin anuiy and hoe componen which were preen in uch minueuaniie ha hey can only hae been preen a impurie om he oreand/or fluxe) Thu he in, inc, iler and lead form one group, and he

nickel, iron, enic, anmony and cobal form he oherThe reulan principle componen plo of he blank analye clearly

how a marked difference beween he wo group The random pread creaedby he in, inc, iler d lead fig3) conra markedly wih he clearcluer creaed by he minor componen fig4)

Fig.3

0.06 5

34004C D 7 229 932

16 0002 - 5 33 8 7

o:1 0 62 8 2: 25 9

-002 r 2

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0.2r-05 7 905 - DD

0 -0.05

8

289

o d' 2E87DD

25

0.05 r

0. 05

22524

-0.2-

00878 00558 0.00525

Fig4

1

0052 00295528

pc

- ra nfd - a j ,

FigS

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OEN[ PELLEl Aoq-rrm - eents

Fg6

Sample Grop

35

38 3

39 2

40 2

41

42 143

44 3

45 3

46 2

47 2

48 3

49 2

g 7

I. " IJ I,

Hghes gropprobably

10000

10000

0000

09999

09999

000009986

0000

0000

10000

09997

0000

10000

.

g

15 8

Second hghesgrop prob.

0000

0000

0000

000

0003

0000004

0000

0000

0000

0003

0000

0000

l8

n order o confrm ha he composonal gropngs enconered aresgncly dfferen and no js aracs of he clserng procedre, e daawere sbmed dscrmnan analyss Ths prcess calclaes he relave

8

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probabiiy of membership of each case o the specifie grop The ressconfrme the aibions in al cases with he pobabiliy of membershipbeing less han 99% in only ree cases This is emonsae in he able forthe pees by or components shown in fig7

Discrminan anaysis can also inicate which variabes are responsibe

for he csering. The majoror conole, eemens responsibe for hesigh variaion picke p in e banks grop in ea (F vaes of 30.34 an 1835 respecivey owever he rea gopings, by he minornconoe, eemens are efine by the coba an nicke conens (F valesof 8410 an 28.05 respecively The gropings of the pees are similarlyefine lea is again responsibe for he gopings base on he conoleelemens togeher wih zinc (F vales 2.30 an 3999 respecivey, an heron conen is confrme as being responsible for he minor eemen

gropings (F vale of 87.10 .Mealographic examinaion of the polishe eges of seece examples

aso sppors e view ha wo very fferen grops of maerial are presenThe visible srcres songy sgges ha he prebanks were casinivialy in mos an hen col worke ino he prepare banks Prebank No25 for example ceary shows a lip where he moen mea hasoverowe he op of he mo. The pelles on he oher han form aifferen poction grop, being proce om cas os of aoy which wehen c ino peles wih a colchise The cs can be ceary seen in anmber of he pieces examine

is impoan o noe ha he o cearly iferen composions of he

banks/prebks he pelles is mache by hese wo toay iferen poction sysems. The blankspreblanks are of a gnmea conainingapprox1.4% zinc; hese were cas inivialy hen hammere o somebeing joine ogeher presmaby o mainain a ceran broa weigh sanarThe peles on he oher h are of a eae high in bonze 13%+ inThese were poce by cing off short enghs from a cas ro of mea hebrieness of the alloy making he process easier Ahogh no exampes werefon in he grop oher fins, sch as Norh Leigh (Knigh 1984 anSprobrogh (Matingy an Dolby 1982 show ha he peets were in allkeihoo esine o have been hammere o ino coin banks an en

sck This aomaically poses a nmber of qesions. Davies (1988 anBoon (1987 bo sgges a m he hoar evience raiae copies graaybecome smaler over he perio of procion, ye in he Fenny Sfor gropwe have boh lae banks an the maerial for pocng he smales pes ofcoin (minims Wha is rresented here? Ceany he ies fon wol havebeen more siable for siking the larger blanks. The siaion is frhercomplica by the fac ha the composiions are so ieren The initiainepreaon of the fin ha been to sgges ha he pees were o have beenmee own cas into prebanks an then hammere o ino the blanksemseves. This was cleary no the case seems as f we have wo ypes ofcopy represe here co be arge ha he pees wo have been mixewih other mea no presente in the hoar o poce a simiar alloy o hebanksprebks Why en go to the obe of casing ros hen cngoff sch sma enghs? Frthermore how wo one expain he simiariieswih the oher maerial menione above? epicaion of he aoys se for

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each gup has shown that the differences in composition would have beensuicient o rend diffnces in colour of the shly stck cons. This featuwoud aso support the suggestion that the compositions represent diferentvalues in terms of the component metals empoyed Maybe e incrasedamount of tin in the pee compensaed for te ducon in size? perhaps

we e just seeing maeial deposited at e time when arge copies gave way minims in that area?

The division of the compositons into major and minor componentscleary demonsates the existence of mo than one batch of aoy being

repesened in e sampes and at e major componens were quie coseyconold. These facs argue songy for two distinct and conoed aloysandards being rpresented in te hoard and that these reae dicty to twodierent si groups and poducon pocesses This is in direct conast eaccepted view of radiae copies whe it is generally thought at no aoyingstandards operated; any old meta being melted down for coins (Boon1988:129)

There is a ce ait in the composition of te radiae copies whichshould be mentioned, d hat is the presence of znc Apat m the eeroichalcum issues (eerii and dupondi of te rst two and a half centuiesAD, zic is only prsent as a ace 01 %) in official base-metal coins Indeedzinc is similary acking in bot of te later outbreaks of copying discussedhere. The radiat copies however seem o consistently conain about 1.5%znc This ait was conrmed rcently by Mke Cowell of the Bitish Museum

rsearch laboraories who analysd two suck copies and tree ofcia radiates

sem-quantiavey by X (Cowll pers comm) Wat is the significance ofhe 1.5% zinc and is the amount puely fortuious or, as its fquency suggestsa desid component? Certainy other Romo-Bitish mealwork can containsimiar amouns of zinc (Bayey 1986384 for exampe) but it is the fact thate same amount is maintained over what appears to be, in the case of FennySatford, e mels of metal The same sort of figure occurs in Mke Cowe'sanalyses te Sprobrough Hoa and te Brauweil Hoard (Ziegler 1983)

It may aso be signifcant that the high tn pelles conan vrtualy nozinc The sul of the analyses RF) of te copies n the Brauwiler hoardshow hat copies wit recorded zinc values of between 15% and 4.% also

nd to have ow n values 2%) d at copies with higher tn values (>2%)have less zinc (

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Rchon, J 1989 Th Statstal Analys of Coostol Data.

New Yo: Chapman an aBoon, G. 1988 Coune con n Roman Bran Co the

Arhaeologst Lonon Seaby pp102188

Dav, J. 1988 Barbou raae a uy o he egular Roman conageo he 270 280 D om ouhe Englan PhD he RengUnvery

ughe, M Cowell, MR & Craock, P. 1976 omc boonechnque n rchaeology Arhaeomety. 181937

Kngh, B 1984 Obervaon on con manuacure a Norh Legh RomanVlla Unpublhe ncen Monumen Lab ReporNo4407

Mangly, B & lby, MJ 1982 he Sprobrough horNumsmat Chronle 1422133

Mey, P 1990 Unpublhe poery repor Mlon Keynerchaeologcal Un

Reece, R1987 Coge n Ron Brtan Lonon: SeabySzonnagh, EL 1981 Samplng meho or repreenave elemenal

analy o nonhomogeneou con M/ohma Ata 1191205Zegler, R 1983 Der Shatzfund von Brauweler Koln Rhenlan-Verlag