*5.2. Textiles*

As mentioned previously, the earliest direct scientific evidence of the shellfish dyeing industry were reported for textile fragments unearthed in Chagar Bazar (18th–16th century BCE) [47] and Tell Mishrife [48] and pottery vessels from Crete (ca. 1800/1700 BCE) [49]. The most recent historical textile dyed with shellfish purple is a Byzantine epitaphios, which is dated to the 14th century CE [42] i.e., roughly about the time of the fall of Constantinople.

Shellfish purple has been identified in several textiles and objects related to the textile industry of antiquity e.g., post sherds [7,30–34,36,42,46–49,58,76–104]. As summarized in Table 2, it has been scientifically proved that the valuable dye was used by the Minoans, Hurrians, Phoenicians, Persians, Greeks (in various periods), Etruscans, Jews, Romans, Sarmatians, Copts-Egyptians, Arabs (pre-Islamic period) and Byzantines. These results show that the shellfish purple dye has a long established history of use that spans roughly 3.5 millennia, as it was used uninterrupted from the prehistoric up to the Byzantines times.


**Table 2.** Identifications of shellfish purple in textiles corresponding to various historical periods.

*Case Study: Identification of Shellfish Purple in a Hellenistic Textile*

In 1987 an excavation was carried out in a burial mount in the area of Lakkoma (Macedonia, Greece), which revealed a large cist tomb dating in the last quarter of the 4th c. BCE (Hellenistic period) [89]. Lakkoma is located around 60 km east of Aigai (Vergina), where the Royal Tomb of Philip II, the father of Alexander the Great, was found. The aforementioned dating of the burial is supported by a golden quarter stater of Philip II [89]. Textile purple residues and other organic materials were found within the tomb and investigated in the past using microscopic techniques [89].

A small piece of the textile residues was treated with hot dimethyl sulfoxide (DMSO) to extract the purple dye, which was analyzed using an established HPLC–DAD method [42,75]. This is the first reported HPLC analysis of a purple textile found in the mainland of Macedonia. The chromatogram is presented in Figure 7. The HPLC peaks corresponding to MBI, DBI and DBIR are dominant in the graph. IND, 6'MBIR and 6MBIR correspond to very small peaks, whereas INR was not detected.

**Figure 7.** Chromatogram of a purple textile sample from the Lakkoma tomb at 288 nm.

It is interesting to note that the HPLC profile in Figure 7 is not very different from that of Figure 5, which is representative of the Minoan purple paints and pigments. Consequently, based on the results of the present study it is reported that no major difference is observed in the chemical compositions of the shellfish purple materials used by the Minoans (Figure 5) and the Macedonians (Figure 7). Apparently this is not a general conclusion; it is an observation based on the chemical results of the tested samples.

#### *5.3. Manuscripts*

The scientific investigation of historical manuscripts is a challenging task. While samples can be removed from large-scale objects with relatively little impact on the integrity of the object, the removal of even tiny samples from manuscripts is practically prohibited. Consequently, the study of historical manuscripts is limited to non-sampling techniques, such as, for instance, XRF [105–108], fiber optics UV-Vis diffuse reflectance spectrophotometry with optical fibres (FORS) [106,108] and Raman spectroscopy [108,109]. Recent advances in the development of non-sampling methods to identify shellfish purple offer new perspectives for the investigation of historical manuscripts, artworks and other objects of the cultural heritage [110,111]. In any case, the limitation to use only non-sampling techniques increases the degree of difficulty in studying manuscripts.

The results reported in the literature do not suggest a widespread use of shellfish purple in historical manuscripts. In particular, the use of shellfish purple has been suggested in very few objects such as, for instance, in a Byzantine (6th century CE) [105], Italian (6th century CE) [106] and Anglo–Saxon (8th century CE) [107] manuscript. The use of shellfish purple was suggested according to XRF results, which revealed the presence of Br [105–107]. FORS results, however, did not confirm the presence of shellfish purple. Analyses yield the information that the chromatic features of manuscripts are dominated by the presence of inorganic and organic colorants other than shellfish purple [105–112].
