4.1. Petrographic characterization: approaching the provenance of the amphorae
From a macroscopic point of view, although ceramics certainly share similarities, especially in the abundant micaceous content, the fabrics are not entirely homogeneous, with a diversity of colors and textures that could perhaps indicate a multiplicity of products. Thin-section petrographic analysis on the selected amphorae enabled the identification of two fabric groups. A full petrographic description of these groups is available in the Supplementary materials, and the discussion here is orientated towards the provenance issue.
Petrographic Group 1 (Fig. 4) includes almost all the samples analyzed (nine out of 10), including the five samples of Almagro 51c amphorae, the two flat-bottomed amphorae, and the two amphorae of the type Ses Fontanelles I (Table 1). The strong similarities in fabric between these nine samples provides evidence of a provenance, most likely, in the same area for all of them. The percentage of coarse inclusions is variable, although never very high, and, in any case, there is a continuous variability between samples with very little coarse fraction and others where it is more common. Similarly, the relative frequencies of the different types of inclusions vary between individuals, although again gradually and always repeating the same range of main inclusions, especially micas (mainly muscovite), monocrystalline and polycrystalline quartz/quartzite, and fragments of metamorphic rocks likely derived from mica-schist, along with other components in minor amounts (Fig. 4).
The typology of the amphorae ―especially in the case of Almagro 51c― points to a provenance either in southern Spain or in Portugal. Comparison with regional geology helps to suggest various possible provenance areas in which there is an important contribution of metamorphic materials, such as the Mediterranean coast of southern Spain (particularly from Málaga to Cartagena), or the Guadalquivir Valley (Aldaya et al. 1972, 1980; Fontboté 1983; Junta de Andalucía 1998; Martín-Algarra 2004). Other areas such as the Atlantic coast of Baetica (e.g., Cadiz Bay), the bay of Algeciras, or southern and western Lusitania could instead be ruled out. In the latter area, corresponding to the lower valleys of the Sado and Tagus, although some rather micaceous fabrics of Late Roman amphorae have been reported (e.g., Mayet et al.1996; Fantuzzi et al. 2015), the comparison with the samples from the wreck of Ses Fontanelles indicates that these are clearly different products, both in terms of clay matrix and texture and composition of the inclusions.
In the case of areas with contribution of metamorphic rocks, it is mainly through comparison with reference materials and previously known fabrics that it is possible to obtain a first insight into the possible provenance based on the compositional compatibility. Thus, the fabrics observed in Petrographic Group 1 are clearly different from those defined in previous studies for the Guadalquivir valley (e.g., Grubessi 1999; Grubessi and Conti 1999; Fantuzzi and Cau 2017, 2019), the coast of present-day Málaga province (e.g., Fantuzzi and Cau 2017; Bernal-Casasola et al. 2020; Fantuzzi et al. 2020), or the coast of Granada (e.g., Vigil de la Villa et al. 1998). Conversely, in the easternmost part of the southern Iberian Peninsula, particularly in the western zone of Cartagena, comparison with previously published studies reveals similarities between our Petrographic Group 1 and the fabrics described for El Mojón workshop (Berrocal 2012: 256–257), where a fine fabric containing predominant inclusions of quartz, muscovite, and fragments of metamorphic rocks rich in quartz and muscovite, as well as iron oxides, has been recorded. It should be noted that we have compared the samples of Petrographic Group 1 with thin sections of four amphorae from the workshops of El Mojón and Mazarrón in Cartagena, and while clear similarities are observed in both the main types of inclusions and textural parameters, some differences are also noticed, especially in the relative frequency of inclusions. In this regard, we should also mention that the samples used as comparison elements are mostly spatheia, with fabrics possibly more refined than in other amphora types. In addition, the frequencies of the different components in the amphorae from El Mojón are very variable (Berrocal 2012: 257), especially in the case of calcite, which might suggest the use of raw materials from various outcrops to produce the amphorae. For all the above, the relationship of the Petrographic Group 1 of Ses Fontanelles with the productions of El Mojón or, at least, of the Cartagena area is a very likely hypothesis, especially when comparing with the information previously published by other authors (Berrocal 2012). It is worth mentioning that the workshops in Cartagena (particularly El Mojón) and Granada (sites of Los Matagallares and Los Barreros, in Salobreña) are the only areas known to date in the Mediterranean coast of Spain with well-documented production of both Almagro 51c amphorae and flat-bottomed amphorae (Bernal-Casasola 1998, 2001; Berrocal 2007, 2012); in the case of Málaga, production of Almagro 51c amphorae is well documented, but not of flat-bottomed amphorae (Bernal-Casasola 1997; Serrano 2004).
On the other hand, in the case of Petrographic Group 2 (Fig. 5), which includes only one of the samples analyzed (DSF277), corresponding to a Keay XIX amphora, the fabric observed in thin section indicates a provenance in an area with a dominant metamorphic contribution, but different from the production area of Petrographic Group 1. The nature of the metamorphic rocks present in this fabric could be compatible with different areas with low to very low grade metamorphism associated with phyllite outcrops, as is the case ―especially― of the bay of Málaga, in relation to the outcrops of the Maláguide Complex (Aldaya et al. 1980; Fontboté 1983; Junta de Andalucía 1998; Martin-Algarra 2004; Serrano and Guerra 2004), and also from other more eastern areas of the southern part of Iberia related to the Alpujárride Complex, where phyllite outcrops can also be found, although in many cases along with other rocks related to a higher degree of metamorphism (Fontboté 1983; Junta de Andalucía 1998; Martin-Algarra 2004).
Comparison with the petrographic reference collection at ERAAUB, as well as with comparative materials found in different publications, shows partial similarities with amphorae fabrics between the Punic and Late Roman periods in the Málaga region, including amphorae of the same type Keay XIX (Fantuzzi and Cau 2017; Fantuzzi et al. 2020). It should be noted that the Málaga coast was, based on the archaeological evidence known to date, the main production area of Baetican Keay XIX amphorae –in addition to the important production centers known in Lusitanian– with various documented workshops (Bernal-Casasola 1997, 2001; Serrano 2004; García Vargas and Bernal-Casasola 2008). There are, however, some differences with the most typical fabrics of coastal Málaga, especially the lower frequency of sedimentary rock fragments (argillites, sandstones, and limestone) in sample DSF277, as well as the absence of some inclusions (serpentinite and pyroxene) that are sometimes –but not always– found in accessory quantities in the products of Málaga due to the proximity of the ultra-mafic complex of the Ronda mountain range (Fantuzzi and Cau 2017; Fantuzzi et al. 2020). However, the characteristics of the metamorphic rocks found in the DSF277 fabric, as well as the other types of inclusions observed –e.g., the fragments of igneous rocks present in an accessory quantity, identical to those documented in other Málaga products (Fantuzzi et al. 2020)– suggest that the fabric of sample DSF277 could correspond to a different variant within the products of the Málaga coast. It is important, in this sense, to note that the amphora DSF277 corresponds to an atypical morphological variant of the Keay XIX type, different from that analyzed in previous petrographic studies (Fantuzzi and Cau 2017). For this formal variant we do not know possible workshops and there is no information concerning the chronological and geographical relationship with respect to the best-known variants of this type. The presence of a particular fabric could respond to various factors: a variant of Keay XIX produced in another pottery workshop in the same region?, use of different clay sources at different chronological times of Keay XIX production?
In any case, it should also be noted that the comparison with reference materials and the geology of other production areas for Keay XIX amphorae ―like the cases of western and southern Lusitania, as well as the Baetican coast between Huelva and the bay of Algeciras, and the coast of Granada― suggests that none of them could be proposed as provenance area for sample DSF277. Something similar happens in El Mojón wokshop in Mazarrón Bay, in the Cartagena area, where amphorae like Keay XIX have also been attested (Berrocal 2007, 2012); in this case, the fabric of sample DSF277 could be compatible from a strictly geological point of view, considering the presence of outcrops of phyllites and quartzites a few kilometers from the site (Espinosa et al. 1974). However, the products of this and other well-known workshops in the area are very different in terms of fabric both macroscopically and petrographically from the amphora DSF277. In summary, the integration of the existing archaeological information on the manufacture of Keay XIX amphorae together with the analytical evidence obtained from this study (and in combination with previous studies), suggest as a most likely hypothesis a provenance around the Málaga coast for the amphora DSF277 recovered at Ses Fontanelles shipwreck. In any case, both the lack of known workshops producing the morphological variant of Keay XIX to which this amphora is related to, and the differences mentioned above with respect to the most typical petrographic fabrics in Málaga amphorae, do not allow us for the moment to provide further details concerning its provenance.
4.2. The study of the ichthyofauna: which fish sauce?
All faunal remains recovered from the amphorae containing fish sauce reveals that the substance was derived almost exclusively from a single species: the European anchovy (Engraulis encrasicolus). The only exception was a hiomandibular bone of sardine (Sardine pilchardus) identified in the sample DSF-231 (Fig. 6). A selection of anatomical elements was used to estimate the minimum number of individuals (NMI) of each sample (Table 5). The anatomical representation of the anchovy is quite similar in all samples. The dentaries and other elements of the cranial region are predominant, with the rest of the appendicular skeleton appearing underrepresented, to a greater or lesser extent. Considering the dentaries as a reference for the minimum number of individuals (NMI), the percentage of representation of the vertebrae has been calculated by dividing the number of vertebrae observed by the expected number of vertebrae (e.g., the anchovy has 46–47 vertebrae, if 65 are observed, the estimated NMI will be equal to 2). The average percentage is 19%, ranging from a maximum of 33.3% (DSF-235) to a minimum of 7.1% (DSF-220). On the other hand, the number of vertebrae appears to be correlated to the estimated number of scales, since in those samples where there are with fewer vertebrae there are also fewer scales.
Table 5
Results of the ichthyofauna analysis, number of remains of anchovies identified. The sample marked with * only counts for the remains recovered at the bottom of the toe of the amphora (fig. X), and those bones attached to the walls of the amphora container have not been considered.
Element | DSF-220 | DSF-231* | DSF-235 | DSF-257 |
Dental (right) | 12 | 12 | 3 | 9 |
Dental (left) | 14 | 15 | 3 | 8 |
Articular | 2 | 2 | 0 | 2 |
Neurocranium | 7 | 11 | 2 | 8 |
Maxillary | 18 | 19 | 5 | 15 |
Cleitro | 14 | 14 | 3 | 9 |
Hiomandibular | 12 | 18 | 3 | 5 |
Vertebra | 9 | 65 | 10 | 51 |
Scales | Few (< 25) | Present (c. 50–100) | Abundant (> 250) | Present (c. 50–100) |
Although it is tempting to suggest that the content of the Almagro 51c amphorae was composed almost exclusively of anchovies’ heads, the embedded content in the resin of the inner walls of the amphora DSF-231 showed various articulated skeletons of anchovy (Fig. 7D, and Table 5), with their ribs and vertebrae still in anatomical position. The cranial parts of these specimens were recovered at the lower wall and toe of the amphora probably because of the detachment of the heads during the micronization process. For this reason, we suggest that, despite the observed partial anatomical representation in most of the samples, the fish sauce was made of whole anchovies.
The sardine found in sample DSF-231 had a total length of 11.4 cm based on the dorsal length of the hiomandibular bone (CRD, Fig. 8) and using the following linear regression: LT = 32.89*CRD + 8.43 (r2 0.931); where LT was the total length and r2 was the coefficient of determination (Assis and Amaro, 2006). In the case of the anchovies, the size range is between 7 and 12.5 cm (n = 36; x = 8.7; CV = 13.5), although the vast majority were individuals with sizes between 8 and 10 cm. Although there are no significant differences in the size of the individuals present in the four samples, the occurrence of some larger fishes is observed in the DSF-235 sample (Fig. 8, small box).
4.3. Organic residue analysis: further investigating the content of the amphorae
Almagro 51c
The amphorae DSF220 (sample 4), Almagro 51c type, displays a painted inscription (titulus pictus) Alunnii et Ausonii NN() liq(uaminis) f < l(o)s informing of its content liquaminis flos (flower of liquamen, a fish sauce). Extract i displays abundant dehydroabietic acid followed by abietic acid, and methylabietate. Extracts ii and iii display very abundant dehydroabietic acid, abietic acid, methyldehydroabietate, 7-oxodehydroabietic acid, and retene is also present. These are markers of Pinaceae products, specifically of pitch obtained burning the wood of Pinaceae trees (Colombini et al. 2005). Retene is the marker of heating. The abundance of abietic acid, which are quite uncommon in archaeological samples, suggests that the pitch could derive from Abies sp or alternatively that the residue is very well-preserved and giving a strong signal, not normally observed in archaeological cases.
The abundance of Pinaceae products makes more difficut to identify other compounds. Nevertheless, extract i displays traces of tartaric and succinic acids, that, considering the context and period studied, indicate that the amphora contained wine or its derivatives (Garnier and Valamoti 2016; McGovern et al. 2017; Pecci et al. 2013, 2020). In extracts i, ii, and iii, palmitic and stearic acid are present, being stearic acid the most abundant. Cholesterol is also present in the sample, while β-sitosterol is absent. Although sterols could derive from post-depositional contamination (Hamman et al. 2018), this could also suggest an animal origin of the content of the amphora. In extract ii also C20:0 and C22:0 are present. These compounds are present in fish but are not exclusive markers of this product. The data indicate an animal origin of the content probably mixed with wine, vinegar, or other wine derivative.
Ses Fontanelles I amphora type
Amphorae DSF002S Fontanelles I type (sample 1), display abundant residues. The oleic acid (C18:1) is the most abundant fatty acid in extracts i and ii, followed by palmitic acid (C16:0). In extracts i and iii there are also short chain fatty acids, being the C9:0 the most abundant and dicarboxylic acids, among which azelaic acid is the most abundant. β- sitosterol is present only in traces in extract i. In general, the profile of the three extracts suggests a plant oil content for the amphora, compatible with olive oil. However, the analyses performed do not allow for the identification of TAGs, therefore we cannot fully confirm the presence of olive oil. Sample 1 is the only sample, among the five analyzed, in which tartaric acid is not identified. This datum reinforces the idea that this type of amphora was carrying a plant oil. Differently from the other analyzed amphorae, where resin/pitch biomarkers are abundant, dehydroabietic acid is present only in traces and there are no markers of the production process of the resin/pitch (i.e., heating or extracting it directly from the wood).
The flat-bottomed amphorae
Three samples were recovered and analyzed from flat-bottomed amphorae. Olives were preserved in amphora DSF267.
The samples from amphora DSF267 (sample 2), DSF274 (sample 3) and DSF272 (sample 5), display abundant dehydroabietic acid followed by abietic acid. Methyldehydroabietate and 7- oxodehydroabietic acid are also present. These are markers of Pinaceae products (pitch) obtained burning the wood of Pinaceae trees. The abundance of abietic acid suggests that the pitch could derive from Abies sp. In sample DSF272 pitch is very abundant, even to the necked eye.
Possibly due to the abundance of Pinaceae products, or because we mechanically cleaned the samples in the laboratory (removing the pitch coating layer that possibly had absorbed most of the residues), it is difficult to identify other compounds in the lipid extracts.
Stearic acid (C18:0), palmitic acid (C16:0), and oleic acid (C18:1) are present in extract ii of DSF267 (sample 2) and DSF274 (sample 3), being C18:1 (oleic acid) the is relatively most abundant among them. However, none of these acids is abundant. β-sitosterol is present in traces in extract i. These data are compatible with a plant oil. However, lipids are not abundant in the two amphorae. This is surprising mainly for DSF267, because olives were recovered in the bottom of the amphora. These data indicate that likely, if olives were preserved in a wine/vinegar medium (see later), they did not release abundant fats or that fatty acids possibly degraded and that possibly the abundance of pitch did not allow the abortion of residues in the pottery matrix. In DSF274, no solid residue was preserved, therefore we do not know if it contained olives.
Extracts i of the three amphorae displayed tartaric and succinic acids. Although tartaric acid is present also in other fruits (i.e., tamarind) (Barnard et al. 2011), it is possible to interpret it as a marker of grape derivatives for the context and period studied (Garnier and Valamoti 2016; McGovern et al. 2017; Pecci et al. 2013; Pecci et al. 2020). The presence of tartaric and succinic acids VEDERE MALICO, CITRICO confirms that the analysed amphorae also contained wine, vinegar, or OTHER derivatives, although it is not possible to differentiate among them. Extract i of samples DSF267 (sample 2), DSF274 also displayed syringic acid. This acid is related to the presence of red wine, however further analyses should be performed to confirm this hypothesis, as syringic acid could also derive from contamination. In general, the data could be compatible with the presence of olives in vinegar/other wine derivative, or with a first wine content of the amphorae and a re-use of at least DSF267 for olives.
Sulfur is present in extracts i and iii of the three amphorae.
4.4. Wood and macroplant remains
Elements of the hull of the vessel
The results of the taxonomic identification of the 20 wood elements analyzed are expressed in Table 5. In short, four different taxa have been identified, three corresponding to conifers, Cupressaceae (cypress and juniper family), Pinus (indeterminate pine) and Pinus t. pinea (Stone pine type); and two to angiosperms, Olea europaea (olive tree) and Laurus nobilis (laurel) (Table 5).
Among the larger elements that make up the hull of the boat only a single genus, Pinus sp, has been documented (Table 5). In two cases, it has been possible to differentiate that these corresponds to stone pine type (Pinus t. pinea) (Fig. 10). In two other cases only the genus, Pinus sp, has been determined. On the other hand, for the small parts of the hull three different taxonomic categories have been identified: Cupressaceae, Olea europaea, and Laurus nobilis (Table 5). In the case of fragments belonging to the family Cupressaceae (Fig. 10) anatomical elements have not been clearly observed to differentiate the genus Cupressus (cypress) and Juniperus (juniper). Similarly, in other cases it has not been possible to clearly differentiate between the two species of angiosperms identified, Olea europaea and Laurus nobilis (Fig. 10).
Table 5
Result of taxonomic identification of recovered wood objects (excluding branches)
Element identified | Conifer indet. | Cupressaceae | Indeterminable | Laurus nobilis | Laurus/Olea | Olea europaea | Pinus sp. | Pinus t. pinea | Total |
Peg 1 | | 1 | | | | | | | 1 |
Peg 2 | | 1 | | | | | | | 1 |
Peg 3 | 1 | | | | | | | | 1 |
Peg 4 | 1 | | | | | | | | 1 |
Peg 5 | | 1 | | | | | | | 1 |
Unknown fragment | | | 3 | | | | | | 3 |
Tenon 1 | | | | | 1 | | | | 1 |
Tenon 2 | | | | | 1 | | | | 1 |
Stanchion | | | | | | | 1 | | 1 |
Stringer | | | | | | | | 1 | 1 |
Pin 1 | | | | 1 | | | | | 1 |
Pin 2 | | | | 1 | | | | | 1 |
Pin 3 | | | | | 1 | | | | 1 |
Pin 4 | | | 1 | | | | | | 1 |
Pin 5 | | | | | | 1 | | | 1 |
Pin 6 | | | | 1 | | | | | 1 |
Rib 105 | | | | | | | | 1 | 1 |
Wood | | | | | | | 1 | | 1 |
Total | 2 | 3 | 4 | 3 | 3 | 1 | 2 | 2 | 20 |
The analysis of the wooden elements of the hull of the boat shows in any case a clear distinction in the woods used for large parts and for those of smaller sizes that formed part of the hull assembly system (pegged, mortise, and tenons).
Other plant remains
Several bunches of herbaceous plants interwoven with twigs, together with branches, were found between the amphorae as dunnage to protect the cargo during the journey. All branches were analyzed, together with some samples of the bunches of herbaceous plants and twigs and three fragments of wood of indeterminate shape and origin also found among the cargo (Table 6).
Table 6
Results of the taxonomical identification of branches and unclassified wooden fragments
Element | Indeterminable | Lamiaceae | Vitis vinifera | Total |
Branch (dunnage) | | 1 | 61 | 62 |
Indeterminate woody fragment | 3 | | | 3 |
Branch attached to stopper | 1 | | | 1 |
Total | 4 | 1 | 61 | 66 |
Most of the branches (n = 61) were fragments of common grape vine (Vitis vinifera, Fig. 11) placed between the amphorae transported by the boat to prevent its movement and collision. One of the small branches was of a different species (DSF 40 sample), a plant in the Lamiaceae family. Two other herbaceous plants reveal the presence of paracytic stomata, in parallel to the axis of the leaf (Fig. 12), long cell structures and short cells could be observed, some of the long ones, with anticlinal walls profusely undulated (Fig. 11). The presence of tomentum was also observed (Fig. 12). This consisted of trichomes of various sizes, apparently single-celled, and especially associated with cells of the nerviations, where they concentrate very densely. Some images show structures that are possibly silica (phytoliths). Thus, the observed material has a diversity of well-preserved cellular elements that could in principle be related to plants in the grass family (Poaceae), but a confirmation using phytolith analysis is already planned.
In addition, tree bark stoppers used to seal the mouths of the amphorae were analyzed. In all cases, the different elements of the cell structure of tree bark could be observed (Fig. 12). However, taxonomic identification beyond the determination of bark (cork) was not possible because of the taxonomic undefinition of this part of woody plants and by the conservation of the samples analyzed. However, due to the size of some of them, both in diameter and thickness, the cork pieces probably come from a tree species with a great development of this organ protecting the trunk. The most plausible hypothesis is that the cork oak (Quercus suber), a tree especially appreciated for its large cork production, was used to prepare the stoppers to seal the amphorae.
Finally, among the materials found on the boat a pinecone was identified according to the size and morphology of its components, mainly the peduncle (element that joins the pineapple to the branch) and the sheaths (Fig. 11). In this case, the morphological elements indicate that it is an Aleppo pine pinecone (Pinus halepensis). It presents a patent peduncle, elongated, and curved, typical of this species. The seminiferous scales have slightly convex apphysis. Finally, the measurements of this pinecone (7.1 x 4 cm) fit quite well within the range of the pinecones of this pine species (6–12 x 3.5–4.5 cm) (Amaral Franco 1989).