Since time immemorial attractive colours have held man's attention. Occasionally he has assigned to them symbolic significance, often as religious or status insignia. The various shades of reds and purples have been especially chosen; some see in them the colour of blood, the sun or fire. The presence of ochre and haematite in Palaeolithic burials may be the first instance of the high regard for these colours.Probably the most famous red–purple colour associated with religion, status and general elitism is the shell-based purple-dye of the ancient Mediterranean, known variously as Royal purple, Tyrian purple or Imperial purple. The recent discovery of crushed purple-dye producing shells at Berenice provided a welcome addition to this field, a study which Alexander Dedekind, in the 1890s, termed “Pourprologie”.Before examining the Berenice shells and their context a brief survey will be made of the world-wide usage of shell purple-dye, its Mediterranean origin and distribution, the basic method of production and the contemporary Mediterranean history of the Berenice finds.Purple-dye is obtained from the hypobranchial gland found in the mantle cavity of living Murex and Thais (or related Purpura and Nucella) marine snails. The purpose of this gland is unclear, though it may be the reason such shells are avoided as food by marine life (and are thus not a useful fish bait). The dye might also be ejected by the mollusc as a defence mechanism, much like the black ink of the octopus or squid. Industrial Exploitation of Murex Shells: Purple-dye and Lime Production at Sidi Khrebish, Benghazi (Berenice)* | Libyan Studies | Cambridge Core Search Probably the most famous red–purple colour associated with religion, status and general elitism is the shell-based purple-dye of the ancient Mediterranean, known variously as Royal purple, Tyrian purple or Imperial purple. The recent discovery of crushed purple-dye producing shells at Berenice provided a welcome addition to this field, a study which Alexander Dedekind, in the 1890s, termed “Pourprologie”. Before examining the Berenice shells and their context a brief survey will be made of the world-wide usage of shell purple-dye, its Mediterranean origin and distribution, the basic method of production and the contemporary Mediterranean history of the Berenice finds. Purple-dye is obtained from the hypobranchial gland found in the mantle cavity of living Murex and Thais (or related Purpura and Nucella ) marine snails. The purpose of this gland is unclear, though it may be the reason such shells are avoided as food by marine life (and are thus not a useful fish bait). The dye might also be ejected by the mollusc as a defence mechanism, much like the black ink of the octopus or squid. Information Type Research Article Information Libyan Studies , Volume 11 , 1980 , pp. Journal of Archaeological Science, Vol. 13, Issue. 5, p. 463. CrossRef Google Scholar Lloyd, J. A. 1989. Urban Archaeology in Cyrenaica 1969-1989: the Hellenistic, Roman and Byzantine periods . Libyan Studies, Vol. 20, Issue. , p. 77. CrossRef Google Scholar McGovern, P E Lazar, J and Michel, R H 1990. The analysis of indigoid dyes by mass spectrometry . Journal of the Society of Dyers and Colourists, Vol. 106, Issue. 1, p. 22. CrossRef Google Scholar Michel, R H Lazar, J and McGovern, P E 1992. The chemical composition of the indigoid dyes derived from the hypobranchial glandular secretions of Murex molluscs . Journal of the Society of Dyers and Colourists, Vol. 108, Issue. 3, p. 145. Journal of Archaeological Science: Reports, Vol. 4, Issue. , p. 320. CrossRef Google Scholar Oliver, Alejandro Valenzuela 2015. An ancient fishery of Banded dye-murex (Hexaplex trunculus): zooarchaeological evidence from the Roman city of Pollentia (Mallorca, Western Mediterranean) . Journal of Archaeological Science, Vol. 54, Issue. , p. 1. CrossRef Google Scholar Szabó, Katherine 2017. Encyclopedia of Geoarchaeology . p. 772. CrossRef Google Scholar Syrides, George E. 2019. Marine and terrestrial molluscs in the sanctuary . Opuscula. Annual of the Swedish Institutes at Athens and Rome, Vol. 12, Issue. , p. 241. ‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply. Find out more about the Kindle Personal Document Service. Industrial Exploitation of Murex Shells: Purple-dye and Lime Production at Sidi Khrebish, Benghazi (Berenice) * Volume 11 David S. Reese DOI: https://doi.org/10.1017/S026371890000858X Your Kindle email address Please provide your Kindle email. @free.kindle.com @kindle.com ( service fees apply ) Available formats PDF Please select a format to save. Industrial Exploitation of Murex Shells: Purple-dye and Lime Production at Sidi Khrebish, Benghazi (Berenice) * Volume 11 David S. Reese DOI: https://doi.org/10.1017/S026371890000858X Available formats PDF Please select a format to save. By using this service, you agree that you will only keep content for personal use, and will not openly distribute them via Dropbox, Google Drive or other file sharing services Please confirm that you accept the terms of use. Cancel Save × Save article to Google Drive To save this article to your Google Drive account, please select one or more formats and confirm that you agree to abide by our usage policies. If this is the first time you used this feature, you will be asked to authorise Cambridge Core to connect with your Google Drive account. Find out more about saving content to Google Drive . Industrial Exploitation of Murex Shells: Purple-dye and Lime Production at Sidi Khrebish, Benghazi (Berenice) * Volume 11 David S. Reese DOI: https://doi.org/10.1017/S026371890000858X Available formats PDF Please select a format to save. By using this service, you agree that you will only keep content for personal use, and will not openly distribute them via Dropbox, Google Drive or other file sharing services Please confirm that you accept the terms of use.

Muricidae molluscs are the source of a valuable purple dye that was traded as a luxury item in the Mediterranean region and by the late Byzantine was reserved for royalty and priests. Less well known is the use of muricid opercula in sacred incense and traditional medicines, although they are still used as rare ingredients today. This study provides the first chemical assessment of opercula from Muricidae, based on several traditional preparation procedures. Chemical analysis of opercula smoke revealed aromatic phenols, which act as fragrance stabilisers and produce a "medicinal" odour. Analysis of lipid extracts revealed pharmaceutically active compounds, including brominated indoles, choline esters and adenosine, consistent with their traditional medical applications. Depending on the preparation procedures, toxic pyridine was also detected. ICP-MS analysis of muricid opercula shows the presence of essential macro and microelements, as well as metals, some of which exceed the recommended safe levels for human use. Nevertheless, these findings support the Muricidae as an historically important marine resource, providing Biblical dyes, medicines and perfume. The opercula contains biologically active compounds and produces smoke containing volatile scent compounds, consistent with their identification as the most likely source of onycha, a controversial ingredient in sacred incense.

In the context of a broad study aimed at examining dyeing technologies in the Timna textiles collection, three samples of prestigious fibers dyed with murex sea snail were identified. Our identification is based on the presence of 6-monobromoindigotin and 6,6-dibromoindigotin components (detected using HPLC analysis), which is considered unequivocal evidence for the use of murex-derived purple dyestuff. Furthermore, by comparing the analytical results with those obtained in a series of controlled dyeing experiments we were able to shed more light on the specific species used in the dyeing process and glean insights into the ancient dyeing technology. The samples originated from excavations at the extensive Iron Age copper smelting site of "Slaves' Hill" (Site 34), which is tightly dated by radiocarbon to the late 11th-early 10th centuries BCE. While evidence for the important role of purple dyes in the ancient Mediterranean goes back to the Middle Bronze Age (early 2nd millennium BCE), finds of dyed textiles are extremely rare, and those from Timna are the oldest currently known in the Southern Levant. In conjunction with other observations of the very high quality of the Timna textiles, this provides an exceptional opportunity to address questions related to social stratification and organization of the nomadic society operating the mines (early Edom), the "fashion" of elite in the region during the early Iron Age, trade connections, technological capabilities, and more. In the context of a broad study aimed at examining dyeing technologies in the Timna textiles collection, three samples of prestigious fibers dyed with murex sea snail were identified. Our identification is based on the presence of 6-monobromoindigotin and 6 , 6-dibromoindigotin components (detected using HPLC analysis), which is considered unequivocal evidence for the use of murex-derived purple dyestuff. Furthermore, by comparing the analytical results with those obtained in a series of controlled dyeing experiments we were able to shed more light on the specific species used in the dyeing process and glean insights into the ancient dyeing technology. Focusing on the dyeing technologies, we applied High Pressure Liquid Chromatography (HPLC) analyses to identify organic dyestuff; we found three items that were dyed with true purple, which is based on extracts from the murex sea snail. True purple—also known as ‘royal purple’—was considered the most prestigious dye for textiles in many ancient societies. The finds from Timna currently constitute the earliest physical evidence on dyed fiber of true purple in the Southern Levant. Dyeing is based on material extracted from the snail’s hypobranchial gland (located under the mollusc’s mantle [ 14 ]), and the exact shade depends on different parameters, such as the chemical precursors compounds of each snail species, the dyeing process, and the levels of oxygen and light that the dye is exposed to [ 15 ]. The dyeing process using murex was a sophisticated, multi-stage process [ 15 ]. It was more complex than dyeing techniques based on plants: The snail-harvest [ 15 , 16 ] and the extraction of the gland from the snail required knowledge of biology and much more efforts than collecting plants in the field [ 17 – 19 ]; murex-based dyeing must take place close to the site from which the snails originate, because the freshness of the material has a significant effect on the results [ 19 – 22 ]; and finally, the dyeing process is long and involves biochemical, enzymatic and photochemical reactions, and requires reduction and oxidation processes that probably took several days [ 19 ]. 10.1371/journal.pone.0245897.g001 Fig 1 Shells of the three species of murex snails. Although most experiments use strong chemical reagents to shorten the process to a few minutes (like in the hydrosulfite vat method, see S1 Appendix ), successful dyeing has been achieved also in experiments based on materials that were available in antiquity [ 17 – 19 , 23 , 25 ]. The murex dye belongs to the ‘vat dye’ group that is not soluble in water, thus it requires an alkaline environment. This was achieved by adding various materials such as natural natron, or wood ash of alkaline plants [ 19 , 26 , 27 ], urine, or even broken shells ( S1 Appendix ). Common evidence of the purple-dye industry in archaeological sites are the heaps of murex shells, from which the dye-glands were removed [ 25 , 50 – 52 ]. Such heaps, however, may be evidence of other uses of the snails, including food, lime productions, ceramic temper material, decoration and more [ 14 , 33 , 53 , 54 ]. Their association with the dyeing industry is typically based on archaeological indicators such as industrial facilities, working surfaces, indicative tools and alike [ 55 ]. Large quantities of crushed shells with a hole in the area of the hypobranchial gland also suggest a deliberate cracking activity as part of the dyeing industry [ 53 ]. haemastoma , is not easy because numerous variables ( e . g . geographical location, age and sex of the snails, the dyeing process, analytical methods employed to record the composition etc.) may affect the reported composition of the purple dye [ 10 , 84 , 92 ]. Nevertheless, it is possible to see a clear trend with respect to the ratios of the dye substances in each species [ 27 , 35 , 58 , 61 , 84 , 91 , 93 ], that helps to identify the species of the murex used in the dyeing of the archaeological textiles with a high level of certainty. trunculus was most probably also used, and this sample therefore represents the double-dyeing process for the production of the expensive dye of Tyrian purple, which was described by Pliny the Elder (NH: IX, 62, 137). According to Pliny, in this method the fiber was dipped into a first bath of ‘ pelagium’ and then into a second bath of ‘ bucinum’ . Although the identification of these species is not certain, it is agreed by all researchers that Pliny refers to two

Until late antique times, murex shells were used for the production of true purple. Murex production sites are found all around the Mediterranean. In this paper are studied four sites from the Balearic Islands. Radiocarbon dates from animal bones and charcoal supposed to be synchronic with the murex dye production, are compared to direct dating of the murex shells. In all but one case the terrestrial samples were inconsistent. The murex shells on the other hand yielded coherent results. The charcoal and the animal bones were without any doubt intrusive.

Abstract Purple is a color between magenta and violet, a deep and often dark color, which was highly valued in antiquity as a symbol of prestige, wealth, and power.