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NON FERROUS METALLURGY AT THE MEDIEVAL CASTLE OF CASTEL MANFRINO

A.Iacone, S. Prosperi, V.La Salvia (Universit di Chieti, DSA)

ABSTRACTThe paper will present the main results of the 2003-2006 excavations referring to copper

production. The various indicators of metallurgical activities will be presented and theproduction process will be explained according to the archaeological evidence.

KEYWORDSCopper, metallurgy, coins, castle, middle ages.

THE SITE OF CASTEL MANFRINO

The site of Castel Manfrino is located at the outset of the valley of the river Salinello, on a rocky

spur at 100 m. above the sea level between the Montagna di Campli amd the Montagna dei Fiori.The still standing medieval castle is placed in an area between the regions ofMarche andAbruzzo

that during this period connected the mountainous valleys with the sea cost. This is why it acquired

an important position within the trade network.1. Presently, three standing towers, placed along the

S-N axis of the rocky ness, and part of the fence are preserved.2 The archaeological excavations of

the years 2003, 2004 and 2006, that were carried out in the zones within the southern and the central

towers, allowed the recognition of the stratigraphic features of the site and thus its history (fig.1). 3

The main archaeological phases are as follows: an early medieval phase attested by the finding ofthe rest of the walls of a small church (N-S oriented) with an irregular perimeter and a horse shoe

like apse.4 Immediately north of this latter structure, a circular hole excavated into the rock was

brought to light. Inside this cavity, there are signs of calcareous concretions and a small waterway

which served it with water. The close relation with the surviving portion of the church may allude

to a baptismal function of this tiny pole. Further north and somewhat higher relative to the previous

structures, though in stratigraphic association, a great quadrangular room has been discovered. The

thickness of its walls (1,30 m. circa) may allow the interpretation of this area as a defensive towerfor the religious building.5 Moreover, a lot of evidence came from the Norman-Swabian period.

1 See, S. ANTONELLI, Inquadramento territoriale, in M. C. SOMMA et alii, Castel Manfrino (TE). Un insediamentofortificato tra Marche ed Abruzzo. Prime indagini archeologiche (2003-2004) , in Temporis Signa, Spoleto (2006), p.2.2 See, M. C. SOMMA,Il castelloe le strutture murarie, in M. C. SOMMA et alii, Castel Manfrino (TE). Un insediamentofortificato tra Marche ed Abruzzo. Prime indagini archeologiche (2003-2004), in Temporis Signa, Spoleto (2006), p.20.3 The surveyed area is known as Saggio II; for the analysis of the written sources see, M. C. SOMMA,Le fonti storiche, inM.C. SOMMA et alii, Castel Manfrino (TE). Un insediamento fortificato tra Marche ed Abruzzo. Prime indaginiarcheologiche (2003-2004), in Temporis Signa, Spoleto (2006), p. 7.4 See G. PANT, Chiese rurali della diocesi di Vercelli , in Chiese e insediamenti nelle campagne tra V e VI secolo, 9

Seminario sul tardoantico e lalto medioevo (Garlate, 26-28 settembre 2002), a cura di G. P. Brogiolo, Mantova, (2003),pp. 87-108, in part. pp. 93-94.5 S. ANTONELLI,Le indagini archeologiche, in M.C. SOMMA et alii, Castel Manfrino (TE). Un insediamento fortificato traMarche ed Abruzzo. Prime indagini archeologiche (2003-2004), in Temporis Signa, Spoleto (2006), p. 10.

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This period marked an evident change in the function of the area under investigation and there is in

fact evidence of craftsmanship and of a general reconstruction of the defensive structures. In this

period, the fortifications include an southern tower connected through a wall to another tower,

which is located immediately north of the early medieval one, which at this time must have already

lost its original function. Actually, this area during this phase is characterized by abundant rests of

charcoal and signs of burning on the walls. This situation, thus, yields evidence of a consistent and

extensive use of fire within the area.6 Accordingly, the finding of two bricks, possibly pertaining

originally to a quadrangular wall which is presently trimmed down, together with various strata of

heavily baked clay and working tools were interpreted as the remnants of a pottery kiln. Other

evidence of craftsmen activity for the same period comes from another room N-W to the southern

tower where the rest of a metallurgical furnace have been found.7 As it is often usual, only the

bottom of the production unit is preserved within the stratigraphic features. Together with the

furnace there is evidence of a work surface that was probably covered with a deck. Moreover,

discard materials, slag, semi-products, abundant rest of charcoal and finished artifacts clearly

indicate that within this area a workshop for non ferrous metallurgy has been located. During the

Angevin period, the castle underwent a deep restructuring that implied a complete revision of the

pre-existing phases and, thus, a severe alteration of the stratigraphy. Such a restructuring phase is

also witnessed by written documents as for the project realized by the architect dAngicourt8 which

implied the extension of the castles walls, the building of the northern tower. In addition to this,

during the same period, between the southern tower and the central one, different rooms were built

that served as residential spaces together with a small chapel. Inside this structure there was a grave

and its wall were painted (these frescos are partially still visible in situ).9

V. La Salvia

THE FURNACE STRUCTURE

6M. TORNESE,Le indagini archeologiche, in M.C. SOMMA et alii, Castel Manfrino (TE). Un insediamento fortificato traMarche ed Abruzzo. Prime indagini archeologiche (2003-2004), in Temporis Signa, Spoleto (2006), p. 17.7 For comparable situations see, C. CUCINI TIZZONI M- TIZZONI, Studiodegli scarti metallurgici, in Archeologia a MonteBarro, II. Gli scavi 1990-97 e le ricerche a S. Martino di Lecco , a cura di G.P. Brogiolo e L. Castelletti, Lecco, (2001),pp. 273-279, in part. p. 274 and E. MICHELETTO,Archeologia dei metalli in Piemonte dallet tardoromana al medioevo .Appunti per una schedatura preliminare, in Miniere, fucine e metallurgia nel Piemonte medievale e moderno , Atti delConvegno (Rocca de Baldi, 12 dicembre 1999), a cura d R. Comba, Cuneo, (1999), pp. 3-20.8 See F. ACETO, Castel Manfrino Castrum Maccle, in La valle del Vomano ed i Monti della Laga = Documenti

dellAbruzzo Teramano III, 1, a cura di L. Franchi DellOrto, Pescara, (1991), pp. 302-303.9 See, D. BERNABEIGli intonaci dipinti della chiesa bassomedievale, in M.C. SOMMA et alii, Castel Manfrino (TE). Uninsediamento fortificato tra Marche ed Abruzzo. Prime indagini archeologiche (2003-2004), in Temporis Signa,Spoleto (2006), p. 39.

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As already mentioned, the archaeological investigation of the area placed N-W of the southern

tower (Room 5), yielded clear evidence of metal production. The severe restructuring of the are

during the Angevin period left in place only the bottom part of the furnace as a semicircular cut

within stratigrafic features. During the 2006 field campaign, a fragment of the inside wall of the

furnace has been discovered. It is characterized by an evident bending. This shape, together with the

comparison of other furnaces fragment incorporated within the slags,10 stands for a cupola form of

furnace with a frontal or lateral entrance for tuyeres.11 Moreover, the stratigraphic analysis of the

walls of the Angevin residence building, which is the strucuture overlapping the original workshop

location, suggest that this production unit should have been operating during a earlier phase, that is

to say the Norman-Swabian period. However, together with the furnaces rests, other findings

support the hypotesisi of the presence of non-ferrous (copper) metal working workshop. During the

excavations within the area 1469 grams of slag were collected. This quantity may not be at all

considered complete: the workshop was located aside the castles walls and this permitted an easy

evacuation of all discard material outside the fence along the western slope of the mountain. In

addition, the geomorphology of the site certainly would have helped the slag in sliding down along

the very mountain slope. This hypothesis is supported by the finding of two slags into the western

cliff. One of these is an iron slag. Its shape is typical for smithy salgs, weights 350 gr. and is

covered with glassy-siliceous crusting. At the moment, it represents the only prove of iron making

within the site. All the slag were macroscopically analyzed and, then, typologically subdivided.12

Accordingly, they were all ascribed to copper production. 25 pieces for a total weight of 83,9 gr.

were identified as tapped slag fragments (Fig. 2), while other 27 slag fragments (1035,5 gr.) were

recognized as internal slag (Fig. 3). The first group present a high grade of viscosity which

witnesses for their fluid state typical for tapping out from the furnace. The other one, is

characterized by irregular shape and charcoal crusting. The relatively small amount of slag together

with the geology of the region, lacking of metal ores, suggest that cupper semi-products were used

as raw material for artifacts production. Supporting this idea is also the findings of a fragments ofcopper alloyed objects,13 possibly bowls, that apparently were not a direct production of the castles

10Some of the slag and bricks fragments together with charcoal and hash traces seems to indicate that the furnacesinternal wall was covered with refractory palster.11For furnaces tipology see, R. PLEINER,Iron of Archeology. The European Bloomery Smelters, Praha, (2000), figg. 2,1,3.1; C.GIARDINO,I metalli nel mondo antico, Roma-Bari, (1998), pp. 60-61.12See, T. MANNONI E. GIANNICHEDDA, Archeologia della produzione, Torino, (1996), pp. 193-196; R. F. TYLECOTE,Metallurgy in Archaeology, London, (1962); C.GIARDINO,I metalli nel mondo antico, Roma-Bari, (1998), pp. 63-6413 For identifyin copper alloyed bowls see,. Arti del fuoco in et longobarda, a cura d M.S. Arena e L. Paroli, Roma(1984), II.9, fig. 20, pp. 48-49; M. C. CARRETTA, Catalogo del vasellame bronzeo altomedievale, Firenze, (1982); P.

PRIN, A propos des vases de bronze copte du VIIe sicle en Europe de lOuest: le pichet de Bardouville (Seine Maritime), in Cahiers Arqueologiques, 40, (1992), pp. 35-50; H. SEDLMAYER,Die rmischen Bronzegefe in Noricum,Instrumentum 10, Montagnac, 1999, ed ancora J. WERNER, Italienisches und koptisches Bronzegeschirr des 6. und 7.Jahrunderts nordwrts der Alpen, in Mnemosynon Th. Wiegand, Mnchen, (1938), pp. 74-86.

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workshop. They appear to have been intentionally broken and made into pieces in order to provide

raw material for melting. The origin of these artifacts is possibly to be found not inside the castle

but for sure in other places that are non contemporary and inconsistent with the workshop activity.

The macroscopic analysis of the some mineral fragments may also suggest that a small scale

smelting activity could have been taking place as well.14 However, also considering the

geographical location of the site relative to the commercial network, one may suppose that the raw

material could have come from either the Colline Metallifere in Tuscany of from the other side of

the Adriatic sea, from the rich ore deposit of the Balkans. Another clue for copper alloyed

production comes from the findings of numerous crucibles15 that have been unearthed from the

destructuring strata of the workshop area. The typology of the fragments of rims and bottoms16 of

the crucibles apparently fits with small-sized objects used for the production of small artifacts.

Supporting this hypothesis is the finding of an entirely reconstructed crucible. Its shape resembles

the frustum of a cone, has a triangular section and the bottom is flat17(fig. 4, 5). Particularly

interesting is the inside crusting rich in slaggy metal (copper alloyed material) and heated earth.

This feature is not an unicum since many other fragments of crucibles bear the same type of internal

crusting whereas the outside is often vitrified. Among the various fragments of crucibles, it is

possible to clearly distinguish a partially reconstructed item with convex bottom,18 (Fig. 4, 1) a

bottom with a portion of the side wall (Fig. 4, 2) six flat bottoms19 (Fig. 4, 3) , six small beak (Fig.

4, 4-6-7), six rims and five walls. Apart from one with a semi-spherical shape, all the other present

a semi-cylindrical or a frustum of a cone form.20

A. Iacone

THE PRODUCTION OF ROUND BARS FOR COINAGE: STRIKING COINS FOR THE

CASTLES DAYILY LIFE

14 Archaeometric analyses will possibly confirm this hypothesis.15The clay used is refractory, porous and relatevely clean with fine clacius carbonate inclusions.16ANTONELLI S., Gli indicatori della produzione metallurgica, in M.C. SOMMA et alii, Castel Manfrino (TE). Uninsediamento fortificato tra Marche ed Abruzzo. Prime indagini archeologiche (2003-2004), in Temporis Signa,Spoleto (2006), pag. 62. The crucibles are small or medium sized objects but one, different in shape with a pot likeform. See, R. J. FORBES, Studies in ancient technology, vol. 8, (Leiden), 1971, p. 122, fig. 25.17TH. REHREN, Crucibles as Reaction Vessels in Ancient Metallurgy in Mining and metal Production. Through the ages, acura di P. Craddock e J. Lang, London (2003), p. 208, fig. 14.2.18For this type of crucible it is possibile to think that it was put on fire handling it with tongs.19For this type of crucible it is possibile to think that it was put directly on the furnace fire.20 See, T. MANNONI A- CUCCHIARA,Indicatori di attivit metallurgiche, in S. Antonino: un insediamento fortificato dellaLiguria bizantina, a cura di T. Mannoni e G. Murialdo, Bordighera, (2001), p. 590 e con quelli di Monte Barro (LE),cfr. C. CUCINI TIZZONI M- TIZZONI, Studiodegli scarti metallurgici, in Archeologia a Monte Barro, II. Gli scavi 1990-97 e le ricerche a S. Martino di Lecco, a cura di G.P. Brogiolo e L. Castelletti, Lecco, (2001), pp. 279-278.

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At the present stage of the investigation, the activity of furnace most represented within the

stratigraphic features of Room 5 is the production of round bar for striking coins. According to the

different striking techniques, it has been possible to define three diverse main categories within

round bars typology:

1a) this group consist of hollow circular items, cut off sheet of copper alloyed matrerialthrough

scissors and then imprinted by a prick (7 items; diameter of 1,4 cm and thickness between 0,7 and 1

mm ), (Fig. 5, 14-18-19-20).

1b) flat round bars with a circular form. They were made through hammering and flattening objects

of the previous typology (5 items; diameter between 1,3 and 1,5 cm; thickness between 0,5 and 1

mm), (Fig. 5, 11-12-13).

2) These objects have an irregular or pseudo-poligonal shape; they were cut off a flat copper alloyed

sheet through scissors (9 items; diameter between 1,1 and 1,4 cm; thickness between 0,6 and 1,2

mm), (Fig. 5, 6-7-8-9-10).

3) Hollow circular artifacts, possibly melted into clay moulds (4 items; diameter of 1 cm and

thickness between 0,6 and 0,8 mm)21, (Fig. 5, 15-16-17).

4) This group consists of quadrangular artifacts cutt off copper alloyed sheets and refurnished

through hammering with a round head hammer (2 items; 1,4 cm long and 1,45 wide; thickness

between 0,5 and 0,8), (Fig. 6, 5-6).

Moreover, during the excavations various fragments of copper alloyed sheet (Fig.5, 1-2-3-4-5) have

been brought to light. Many of them bare evidence of cutting edges that correspond to the shape of

typology 1a, 1b and 2. As far as the third group is concerned, the finding of a refractory clay (Fig. 5,

21) mould apparently goes exactly in this direction. The mould presents three cavities, the first of

which is connected through a small channel to a triangular opening at the rim of the same object. It

also has two different holes diametrically opposing each other. These were possibly use to ease the

closing of the mould with another overlapping piece.22 The round bar of group three, actually,

perfectly match with the mould cavities and present an remarkable uniformity in diameter.Moreover, other two refractory clay (Fig. 6, 1-2) moulds have been discovered which were

possibly used for producing small copper bars.23 Always referring to coinage are the findings of

metal bars, sheets and conglomerations (3 items). These artifacts, referring to our group 4, find their

matching items in the production of a clandestine mint attested in Tuscany at the site of

21See, L. TRAVAINI, La monetazione dellItalia normanna, Roma, (1995), pp. 233-234; A. FINETTI, Numismatica etecnologia, Roma, (1987), p. 31; S. BENDALL D. SELLWOOD, The Metod of Striking Scyphate Coins Using Two ObverseDies, in The Numismatic Chronicle, CXXXVIII (1978), pp. 93-104.22 Riguardo allutilizzo di matrici per la monetazione cfr. A. FINETTI,Numismatica e tecnologia, Roma, (1987), p. 30eN. VISMARA,Do ut des (monete, scambi e banche dallantichit ai giorni nostri), Bergamo, (2005) p. 10.23See, D. GH. TEODOR, Tipare din secolele VI-XI D. HR. In Regiunile Carpato-Nistriene, inArheolgia Moldovei XXXVIII2005, Bucuresti (2005), pp. 168 fig. 8.

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Castellaccio in Garfagnana which was striking denari of the city of Lucca and Genoa. Here as

well, the production process consisted of melting some kind of copper alloyed conglomerations in

order to obtain small ingots (Fig. 6, 3); these were later flattened (Fig. 6, 4) by hammering into

sheets.24. After this phase, quadrangular round bar were cutt off and then put into shape through

hammering with a rounded head hammer. One of the side did not suffer the beating since it was

hold by the tongs.25 It may not be, thus, by chance that a denario fromLucca was found at Castel

Manfrino;26 after a macroscopic analysis it was apparently struck through the method described

above. At the present stage of research, no punches have been found. However, there might be

indirect proves of their presence. Actually, various iron sticks (see fig.) have been found. These

objects present a quadrangular section finishing into a pyramidal point identifiable only for one

single item. The opposite point appears to be flattened thanks to continuous hammering which had

suffered. These artefacts could be interpreted as the punch for preparing the minting die. In addition

to this, an elliptical and worn sandstone file was found not far from the workshop location and it

might be used to sharpen the very punches.27 The vast majority of the round bars do not bear strong

marks of striking. Only 4 items, pertaining to group 1b, 3 and 4 present some evidence of punching.

The first apparently has a cross one the one side and an engraved line on the other. The other one,

has signs of indentations. As for the last two, one presents indentations as well, while the other a

flower like image.

S. Prosperi

24A. FINETTI, Numismatica e tecnologia, Roma, (1987), pp. 27-36; F. PANVINI ROSATI , La tecnica monetariaaltomedievale, in Artigianato e tecnica nella societ dellalto medioevo occidentale, Atti della XVIII Settimana distudio del Centro italiano di Studi sullAlto Medioevo, Spoleto, (1970), II, pp. 715-716, in part. p. 729; G. C IAMPOLTRINI,P. NOTINI, G. ROSSI, Una zecca abusiva del XII secolo in Garfagnana, in I luoghi della moneta. Le sedi delle zecchedallantichit allet moderna, Atti del Convegno Internazionale (Milano, 22-23 ottobre 1999), Milano (2001), pag.246 fig. 9a, 9b, 9c, 9e, 10.25See, G. CIAMPOLTRINI, P. NOTINI, G. ROSSI, Una zecca abusiva del XII secolo in Garfagnana, in I luoghi della moneta.Le sedi delle zecche dallantichit allet moderna, Atti del Convegno Internazionale (Milano, 22-23 ottobre 1999),Milano (2001), p. 236.26 DALESSANDRO G., i reperti monetali, in M.C. SOMMA et alii, Castel Manfrino (TE). Un insediamento fortificato traMarche ed Abruzzo. Prime indagini archeologiche (2003-2004), in Temporis Signa, Spoleto (2006), p. 51 inv m. 03; itis worth to mention that among the the findings of glass vessels of Castel Manfrino there are some items that have theircomparison with artifacts of Tuscan origin. In this respect see, T. P RIORE,La suppellettile da mensa, in M.C. SOMMA et

alii, Castel Manfrino (TE). Un insediamento fortificato tra Marche ed Abruzzo. Prime indagini archeologiche (2003-2004), in Temporis Signa, Spoleto (2006), p. 38.27 See, G. VICINO G. MURIALDO, Gli utensili litici, in S. Antonino: un insediamento fortificato della Liguria bizantina, acura di T. Mannoni e G. Murialdo, Bordighera, (2001), pp. 559-561, p. 566, tav. 84, fig. 44, tipology 3f.

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Fi . 1

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Fig. 2

Fig. 3

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I disegni dei crogioli sono stati relizzati da D. Bernabei (1-2-3-4-6-7) e L. Gianvito (5)

Fig. 4

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Fig. 5

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Fig. 6

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