Asio otus: A Long-eared Owl spotted in Abu Dhabi for the first time in over two decades.

Nine species of Owls have been recorded in the United Arab Emirates, although only six of these are considered to by indigenous. Long-eared Owls, Asio otus, are a migratory species found across temperate regions of Europe, Asia, and North America. In the Middle East they have been recorded to breed in northernmost Syria, Israel, Lebanon, and the northwestern part of Iran. They are also occasional visitors to other parts of the region, including the United Arab Emirates, where they are considered to be vagrant and extremely rare. Between 1971 and 2013, there were sixteen recorded sightings of Long-eared Owls in the United Arab Emirates, although the species has not been recorded since.

In a paper published in the Journal of Threatened Taxa on 26 May 2025, Shakeel Ahmed and Sálim Javed of the Environment Agency – Abu Dhabi, report the sighting of a Long-eared Owl in the Al Wathba Wetland Reserve in Abu Dhabi on 1 January 2022.

The 1 January 2022 sighting is the first recording of a Long-eared Owl in Abu Dhabi since October 1999, when another Owl was spotted in the Al Wathba Wetland Reserve. The Owl was spotted at about 6.30 am on the northern part of the reserve. The previous day the area had been hit by a storm, with high winds and heavy rain lasting all day.

An  adult  Long-eared Owl, Asio otus, roosting on a tree in Al Wathba Wetland Reserve. Muhammad Maqsood in Ahmed & Javed (2025).

Long-eared Owls are classified as being of Least Concern under the terms of the International Union for the Conservation of Nature's Red List of Threatened species. Nevertheless, the global population of the species is known to be declining, which, among other things, means that sightings on the fringes of the species range are becoming rarer.

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Felis chaus: Observations of the Jungle Cat in by the lower reaches of the Jordan River, Jordan.

The Jungle Cat, Felis chaus, is a medium-sized Felid found in wetlands across the Middle East, Caucasus region, South and Southeast Asia, and southern China. It is not currently considered globally threatened, but is known to be in decline across its range due to the ongoing loss of wetland habitats. In Jordan the species is currently considered to be Critically Endangered, with the last known record of the species being two dead specimens found in February 1998, on Al–Baqurah Island in the Yarmouk River Valley. However, much of the key environment for the species is found along the Jordan Valley, much of which has been designated a military zone with very limited access.

In a paper published in the Journal of Threatened Taxa on 26 July 2024, freelance conservationists Ehab Eid and Mohammed Farid Alayyan of Amman in Jordan present new evidence for the presence of the Jungle Cat in the Jordan Valley of Jordan, based upon camara trap evidence gathered during a survey targeting the Golden Jackal, Canis aureus.

The camera traps were placed on a private farm growing Citrus fruit at Sheikh Hussein, in the north of the Ghor region, between the Sea of Galilee and the Dead Sea. The boundaries of the farm extend to the Jordan River, where there is an area of wetlands dominated by Common Reeds Phragmites communis, Cattails, Typha domingensis, and Athel Trees, Tamarix aphylla. The area is also home to other wetland Plants, including Sieber’s Wormwood, Artemisia sieberi, Christ’s Thorn Jujube, Ziziphus spina-christi,  Arabian  Fagonia, Fagonia  arabica,  and  Common  Mallow, Malva sylvestris. The area is an important refuge for migratory Birds such as Ducks, Herons, Egrets, and Storks, but is not subject to any form of protection, with the water being affected by herbicide and fertilizer run-off from local farms, and Reed-beds subjected to frequent clearing by farmers who perceive them as a fire-hazard.

Eid and Alayyan placed four camera traps in the Reed beds between June 2020 and 28 February 2022. There were mounted between 40 and 50 cm above the ground, and faced both north and south, to avoid false records during  sunrise  and  sunset. No bait was placed, and the cameras were checked monthly.

During this period, five observations of Jungle Cats were made, with all four cameras making observations. The first observation was made on 12 January 2021 at 12.58 in the afternoon, the second on 17 January 2021 at 9.33 in the evening, the third on 11 April 2021 at 21.35 in the evening, the forth on 3 September 2021 at 10.41 in the evening, and the final observation on 30 January 2022 at 2.12 in the morning.

Jungle Cats photographed in the study area between 12 January 2021 and 30 January 2022. Ehab Eid in Eid & Alayyan (2024).

The camera traps also imaged several other species, including Golden Jackal, Canis aureus, Egyptian Mongoose, Herpestes ichneumon, Wild Boar, Sus scrofa, Red Fox, Vulpes vulpes, and numerous Rodents and Birds, as well as four feral Dogs living on the farm.

To the best of Eid and Alayyan's knowledge, this is the first camera trap survey carried out in the Jordan Valley, and has established the presence of the Jungle Cat in Jordan 22 years after the previous  record, of dead Animals, although the data gathered was not sufficient to determine the number of Cats in the area.

Despite the heavy agricultural activity in the area, it appears to remain a suitable environment for Jungle Cats, with dense vegetation along riverbeds and an abundant supply of Rodents, the favoured prey of Cats.

Jungle Cats were only observed a very limited time, despite the long duration of the study, although this is at least in part due to the dense vegetation in the study area, which proved a general hindrance to observations, interfering with observations of Animals and producing numerous observations of swaying Plants. However, Eid and Alayyan suggest that it is this dense vegetation which makes the environment suitable for Jungle Cats, which are known to be averse to encounters with Humans. 

While Jungle Cats are still persisting in the Jordan Valley, their habitat is threatened by Human activities, with agricultural expansion altering the environment, causing the Reed-beds to fragment and degrade. 

During the time when the study was being carried out, a Jungle Cat was also recorded at Al-Mashare’e, about 6 km to the south of the study area, where it became entangled in a Chicken-protection net, being videoed before escaping. Based upon this, Eid and Alayyan propose that a citizen-science approach, in which residents of the Jordan Valley are encouraged to report sightings of Jungle Cats, may reveal more about the presence of, and threats faced by, the species in the region.

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Nannotanyderus granieri: A new species of Primitive Crane Fly from Early Cretaceous Lebanese Amber.

Primitive Crane Flies, Tanyderidae, are a widely distributed group of mostly aquatic True Flies, Diptera, generally thought to be a relict group. There are 39 living species in ten genera found around the globe, with 34 fossil species dating as far back as the Early Jurassic, which show a greater morphological diversity than is found in the group today. Larval Primitive Crane Flies are typically found in aquatic or semi-aquatic environments, such as wet sandy soil and the outer layers of submerged rotting logs in streams. Adults vary between about 5 mm and about 35 mm in length, and typically have a mottled pattern on their wings, conspicuous mouthparts, and elongated cervical (neck) sclerites.

In a paper published in the journal Carnets Geol. on 1 April 2024, Dany Azar and Sibelle Maksoud of the State Key Laboratory of Palaeobiology and Oil Stratigraphy at the Nanjing Institute of Geology and Palaeontology, and the Natural Sciences Department at the Lebanese University, Di-Ying Huang, also of the State Key Laboratory of Palaeobiology and Oil Stratigraphy at the Nanjing Institute of Geology and Palaeontology, Mounir Maalouf, also of the Natural Sciences Department at the Lebanese University, and Chen-Yang Cai, again of the State Key Laboratory of Palaeobiology and Oil Stratigraphy at the Nanjing Institute of Geology and Palaeontology, describe a new species of Primitive Crane Fly from Early Cretaceous Lebanese Amber.

The new species is placed in the genus Nannotanyderus, which contains six previously described species from the Early Jurassic to Early Cretaceous of Germany, England, Kazakhstan, Mongolia, and Lebanon, and given the specific name granieri, in honour of Bruno Granier, whose research has significantly advanced the dating of amber outcrops in Lebanon. The species is described from a single female specimen, preserved in a piece of amber from the Bqaatouta outcrop in Caza District, which also includes a Spider and a male Chironomid Dipteran.

Nannotanyderus granieri, holotype, female, specimen number BKT-11A.  (A) Habitus, right lateral side. (B) Habitus, left lateral side. (C) Head photomicrograph with confocal microscope. (D) Wing photomicrograph with confocal microscope. (E) Female terminalia, photomicrograph with confocal microscope. (F) Female terminalia, photomicrograph with compound microscope. Scale bars are 500 µm (A), (B), & (D), 100 µm (C), and 50 µm (E) & (F). Azar et al. (2024).

Nannotanyderus granieri is tiny compared to modern Primitive Crane Flies, measuring only 1571 µm in length. making it the smallest known member of the Tanyderidae (the next smallest, measuring only 1890 µm, is Nannotanyderus ansorgei, also from Lebanese Amber). It lacks an elongated neck, but does have well-developed mouthparts, with sclerotized maxillae longer than the head.

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Middle East Respiratory Syndrome Coronavirus reported in the United Arab Emirates.

On 10 July 2023, the United Arab Emirates, notified the World Health Organization of a case of Middle East Respiratory Syndrome Coronavirus in a 28-year-old male from Al Ain city in Abu Dhabi, according to a press release issued by the World Health Organization on 12 July 2023. The case had no history of direct or indirect contact with Dromedaries, Goats, or Sheep (the Animals believed to be the main vectors for the Virus). The patient was admitted to the hospital on 8 June. A nasopharyngeal swab was collected on 21 June and tested positive for Middle East Respiratory Syndrome Coronavirus by polymerase chain reaction (on 23 June 2023. All 108 identified contacts were monitored for 14 days from the last date of exposure to the Middle East Respiratory Syndrome Coronavirus patient. No secondary cases have been detected to date. 

Since July 2013, when the United Arab Emirates reported the first case of MERS-CoV, 94 confirmed cases (including this new case) and 12 deaths have been reported. Globally, the total number of confirmed Middle East Respiratory Syndrome Coronavirus cases reported to the World Health Organization since 2012 is 2605, including 936 associated deaths.

The World Health Organization continues to monitor the epidemiological situation and conducts risk assessments based on the latest available information. The World Health Organization expects that additional cases of Middle East Respiratory Syndrome Coronavirus infection will be reported from the Middle East and/or other countries where Middle East Respiratory Syndrome Coronavirus is circulating in Dromedaries.

The World Health Organization re-emphasizes the importance of strong surveillance by all Member States for acute respiratory infections, including Middle East Respiratory Syndrome Coronavirus, and to carefully review any unusual patterns.

On 10 July 2023, the International Health Regulations National Focal Point of the United Arab Emirates notified the World Health Organization of a confirmed case of Middle East Respiratory Syndrome Coronavirus in Abu Dhabi. The patient is a 28-year-old male, non- Emirati national living in Al Ain city, a non-healthcare worker.  The case visited a private medical centre multiple times between 3 and 7 June 2023, complaining of vomiting, right flank pain, and dysuria (pain when passing urine). On 8 June, the case presented to a government hospital with vomiting, and gastrointestinal symptoms including diarrhoea, and was given an initial diagnosis of acute pancreatitis, acute kidney injury, and sepsis.

On 13 June, he was in critical condition and referred to an intensive care unit (at a specialized government tertiary hospital where he was put on mechanical ventilation. He deteriorated and a nasopharyngeal swab was collected on 21 June and tested positive for Middle East Respiratory Syndrome Coronavirus by polymerase chain reaction on 23 June 2023.

The case has no known co-morbidities, no history of contact with Middle East Respiratory Syndrome Coronavirus Human cases, and no recent travel outside the  United Arab Emirates. The patient has no known history of direct contact with Animals including Dromedary Camels, nor consumption of their raw products.

All 108 contacts that were identified have been monitored for 14 days from the last date of exposure to the Middle East Respiratory Syndrome Coronavirus patient, no secondary case was identified. The case has no family members or household contacts identified in the United Arab Emirates.

Prior to this notification, the last Middle East Respiratory Syndrome Coronavirus infection reported from the United Arab Emirates was in November 2021. The first laboratory-confirmed case of Middle East Respiratory Syndrome Coronavirus in United Arab Emirates was in July 2013. Since then, the United Arab Emirates has reported 94 cases of Middle East Respiratory Syndrome Coronavirus (including this current case) and 12 associated deaths (a Case Fatality Ratio of 13%).

Middle East respiratory syndrome is a viral respiratory infection that is caused by a Coronavirus called Middle East Respiratory Syndrome Coronavirus, a form of single-strand RNA Virus. Humans are infected with Middle East Respiratory Syndrome Coronavirus from direct or indirect contact with Dromedary Camels who are the natural host and zoonotic source of the Middle East Respiratory Syndrome Coronavirus infection.

Structure and genomic organization of a Middle East Respiratory Syndrome Coronavirus Viron. Bleibtreu et al. (2020). 

Middle East Respiratory Syndrome Coronavirus infections range from asymptomatic or mild respiratory symptoms to severe acute respiratory disease and death. A typical presentation of a person with Middle East Respiratory Syndrome Coronavirus disease is fever, cough and shortness of breath. Pneumonia is a common finding, but not always present. Gastrointestinal symptoms, including diarrhoea, have also been reported. The Virus appears to cause more severe disease in older people, persons with weakened immune systems and those with chronic diseases such as renal disease, cancer, chronic lung disease, and diabetes. Severe illness can cause respiratory failure that requires mechanical ventilation and support in an intensive care unit resulting in high mortality.

No vaccine or specific treatment is currently available, although several Middle East Respiratory Syndrome Coronavirus-specific vaccines and treatments are in development. Treatment is supportive and based on the patient’s clinical condition.

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Analysing silver from Phoenician hoards.

From about 4000 BC onwards the use of silver became widespread in the ancient world. This was obtained by smelting lead-ores in a furnace, and then cupellatiting (oxidising) the resultant metal to separate silver and gold. Lead ores, generally galena (lead sulphate) and cerussite (lead carbonate), were typically mined by a deep pit method, digging vertically down to a seem then following it horizontally. Silver  was important to many ancient peoples, among whom were the Phoenicians, who built city states such as Tyre, Sidon and Byblos, ‘Akko and Dor in Lebanon and on the northern shores of the southern Levant during the Iron Age, roughly from the eleventh century BC onwards, and who travelled widely on trading expeditions, bringing innovations such as the alphabet, murex-based purple dyeing and masterful craftsmanship to the western Mediterranean, where they established colonies in North Africa, Sardinia and Iberia. In the ninth century BC the Phoenicians began to exploit jarosite (potassium-iron sulphate) ores in Iberia, from which silver was also extracted as a biproduct.

Cupellation remained the most common way to obtain silver throughout the classical period, producing silver that still contains small amounts of lead. This is useful to modern archaeologists, who can use lead-isotope analysis to determine the source of silver. Other elements tend to be largely purged from the silver by this method, although gold and bismuth isotopes have sometimes been used to determine the origin of silver. 

Silverware was widely used as a trade commodity in the Near East before the adoption of coinage, with more than 40 silver hoards dating to between 2000 and 600 BC having been unearthed in the southern Levant.

In a paper published in the journal Applied Sciences on 12 January 2022, Tzilla Eshel of the Zinman Institute of Archaeology and School of Archaeology and Maritime Cultures at the University of Haifa, Ofir Tirosh of the Fredy and Nadine Herrmann Institute of Earth Sciences at the Hebrew University of Jerusalem, Naama Yahalom-Mack of the Institute of Archaeology at the Hebrew University of Jerusalem, Ayelet Gilboa, also of the Zinman Institute of Archaeology and School of Archaeology and Maritime Cultures at the University of Haifa, and Yigal Erel, also of the Fredy and Nadine Herrmann Institute of Earth Sciences at the Hebrew University of Jerusalem, present the results of a study which used lead and silver isotopes in silver artefacts to show changes in the source of silver reaching the southern Levant over a period of almost 1500 years, spanning the Bronze and Iron ages.

 

Map of the Southern Levant showing sites with Bronze and Iron Age silver hoards. Svetlana Matskevich in Eschel et al. (2022).

Examination of the lead isotope content of 250 silver items from 22 hoards suggests that Middle Bronze Age items (dating from between 2000 and 1550 BC), were made using silver from Anatolia and the Aegean. In the Late Bronze Age (from about 1550 to about 1250 BC), a time when gold probably replaced silver as the main trading currency, silver from the mines of Laurion (about 50 km south of Athens) begins to appear. During the Early Iron Age (roughly 1200 to 950 BC), following the end-Bronze Age collapse, silver appears to have been rare in the region, and was frequently adulterated with high lead content copper, making it hard to identify the origin of the artefacts. From about 950 BC onwards, Phoenicians revived the trade in silver, importing the metal from the Taurus mountains in Anatolia, and from Iglesiente in south-west Sardinia and later from the Pyrite Belt in Iberia, then from 630 BC onwards Greek traders slowly supplanted the Phoenicians, bringing in silver and copper from Laurion and Siphnos in the Aegean. 

This fits well with the previous understanding of the trade in sliver in the ancient Mediterranean Basin, but only gives a broad view of the geographic areas from which silver was being imported to the region; it does not shed any light on development of silver production practices and the exploitation of new ores. For this purpose, Eschel et al. turned to silver isotopes, which have a number of advantages in the tracing of the origin of ores. Silver will fractionate isotopically during supergene weathering; that is to say weathering caused by oxidation of minerals as water percolates through the rock in near surface environments, as well as during the formation of salts and sulphosalts. The upshot of this is that the proportion of different silver isotopes can vary even within different parts of the same mine, potentially giving a very high resolution way of determining the origin of the metal, and at very least, it is usually possible to tell the difference between silver minerals that formed in deep or shallow environments, with those that formed hydrothermally in shallow environments typically having a higher proportion of the heavier isotope silver¹⁰⁹ than those from deeper environments. 

This method has been applied previously to Hellenistic, Roman, and Medieval coins with some success, but not to pre-coinage silver hoards. As well as studying the origin of silver in Bronze and Iron Age hoards, Eschel et al. were able to study how the way in which the silver was preserved altered the isotopic ratio of the metal. It has previously been shown that the patterna on silver coins is isotopically lighter than the coins themselves, as the lighter isotope silver¹⁰⁷ is preferentially consumed in the making of silver sulphates. The silver from the Levantine hoards was stored in different ways, with some hoards stored in ceramic vessels, some in cloth bundles, and some in both, offering different levels of protection against intrusions by ground-water, which will tend to re-mineralise silver, altering its isotopic composition.

 

Silver hoards analysed in the study: (a) silver from the Shiloh hoard (without pendant), courtesy of the Israel Museum, Jerusalem. (b) Silver from hoard Tell el-‘Ajjul 1312, courtesy of the Israel Antiquities Authority. (c) The Dor silver hoard, the Israel Museum and the Tel Dor Expedition. (d) The ‘Akko silver hoard. (e) The ‘Ein Hofez silver hoard image courtesy of the Israel Antiquities Authority. (f) The ‘Arad silver hoard, courtesy of the Institute of Archaeology at Tel Aviv University. (g) Selected items from ‘Ein Gedi hoard, the Israel Museum, Jerusalem. Eschel et al. (2022).

Eschel et al. chose 45 silver artefacts for silver isotope analysis, all of known chemical and lead isotopic compositions and generally not suspected to be alloyed or mixed with metals from different sources. 

The oldest of these items came from the Middle/Late Bronze Age transitional period (roughly 1650-1500 BC) sites at Shiloh on the West Bank and Tell el-‘Ajjul in the Gaza Strip. The precise origin of these hoards is unclear, but both have jewelery with Anatolian motifs and lead isotopic analysis has suggested that the silver came from Anatolia or the Aegean. Both hoards were found wrapped in cloth bundles.

Silver from the Iron Age (roughly 950-700 BC) hoards at Dor, south of Haifa on Israel's Mediterranean coast, and ‘Akko in the coastal plain region of the Northern District of Israel, have been shown to come from Iglesiente, on southwest Sardinia, and have been associated with Phoenician trading in Anatolia and Sardinia in the Iron Age. The Dor hoard was found wrapped in a bundle, then placed within a ceramic vessel which was covered by a bowl, the 'Akko hoard was simply placed within a ceramic pot.

Silver items from the Iron Age (roughly 950-700 BC) hoards at ‘Ein Hofez inthe Carmel Mountains of northern Israel and 'Arad in the Southern District of Israel, on the border of the Negev and the Judean deserts have been shown to contain lead from Rio Tinto in Iberia, although this is only provides an approximate location for its origin, since jarosite ores from several parts of Iberia are known to have been brought to Rio Tinto for processing with lead. Other items from the ‘Ein Hofez hoard contain lead from Linares and other parts of Iberia, with one item coming from Anatolia. 

The Late Iron Age (roughly 630-586 BC) hoard from ‘Ein Gedi, in Israel west of the Dead Sea, near Masada and the Qumran Cave, contains silver placed unbundled within a cooking pot, covered by a ceramic lamp under the floor of a room. The lead in this silver indicates that it comes from Laurion in Greece, suggesting that it was brought to the area by a Greek trader.

Combining the silver and lead isotope analyses strongly suggests that the Phonicean hoards of Dor, ‘Akko, ‘Ein Hofez and Arad contain silver from Sardinia, Iberia and Anatolia, while the Late Iron Age hoard from ‘Ein Gedi contains Aegean silver, and the earlier, Bronze Age hoards of Shiloh and Tell el-‘Ajjul contain a mixture of Anatolian and Aegean silver. The isotopic ratios of the silver items from Phoenician hoards showed predominantly ratios consistent with having come from hypogene ores, that is to say ores that formed deep within the Earth, which had not undergone significant weathering related isotopic fractionation, whereas the isotopic ratios seen in the earlier Bronze Age and later Greek hoards showed more fractionation, probably indicating that they came from shallower ores which had undergone some surface weathering. 

While all the samples used were taken by drilling into the items to extract silver free from corrosion, some of the items still showed signs of sliver chloride formation at the level from which the sample was taken. This is symptomatic of corrosion through exposure to chlorine ions in groundwater, indicating that these samples were less protected from the environment than other samples. This was found in items from the hoards from Tell el-‘Ajjul, ‘Akko, and ‘Ein Hofez. The silver from Shiloh, Dor, ‘Arad and ‘Ein Gedi were apparently better protected. 

Based upon these findings, Eschel et al. were able to make the following observations. 

Hoards sealed in ceramic vessels were predicted to be best protected against contact with the soil and groundwater within it. The hoards from Dor (which was sealed in a vessel and bundled in cloth, and Ein ‘Gedi, which was sealed in a vessel but not bundled, showed no signs of corrosion, and therefore were apparently protected as expected.

Hoards wrapped tightly within cloth bundles were predicted to be less well protected against groundwater, though it was likely that the silver in the middle of the bundle would be protected somewhat by the silver around it. This would include the hoards at ‘Arad, which was tightly bundled and placed within a ceramic vessel, and which showed no signs of corrosion, and Shiloh, which was bundled but not placed within a vessel, where again no signs of corrosion were found.

Hoards placed within unsealed ceramic vessels were thought likely to be less well protected against groundwater. This included the hoards from ‘Ein Hofez and ‘Akko, both of which showed signs of corrosion.

Finally, silver which was neither bundled nor placed in a vessel was thought to be at the greatest risk of corrosion due to contact with the soil and groundwater. This was the case only with the hoard from Tell el-’Ajjul, which again showed signs of silver chloride formation.

The hoards from Tell el-‘Ajjul, ‘Akko, and ‘Ein Hofez all showed greater isotopic fractioning, which was taken as a sign of the silver in them having come from shallow ore sources, where this could occur prior to the silver being mined. Eschell et al. also note that the silver from these hoards also appeared to be less pure, and suggest that these combined may be a sign that they have been altered after deposition by their original owners, rather than evidence of a different mining origin or smelting technique to the other material.

Eschell et al.'s findings suggest that native silver (silver found in a pure state, which typically comes from deep, hypogene sources) was quite rare in the ancient world, and that most of the silver used came from shallow, supergene sources,

The Phoenicians are known to have brought silver to the Levan from the mid-10th century BC onwards, and from Iberia during the ninth and eighth centuries BC. It is unclear whether the Phoenicians themselves were the drivers of the improving metallurgical techniques being used in the areas where they traded, or whether they were just skilled traders able to aquire this silver and ship it across the Mediterranean. Anatolia is known to have been major centres of silver production from about the third millennium onwards, but the amount of silver being exported appears to have rapidly grown during the Phoenician era. Silver confidently assigned to a Sardinian origin is often found in Phoenician hoards, but no ancient mineworking have been discovered in Sardinia, so it is unclear when mining started there. Silver extracted in Iberia, in contrast, appears to have been exclusively developed by the Pheonicians, who targeted deep, low-lead ore bodies in the Iberian Pyritic Belt from about 800 BC onwards. The Romans began exporting silver from Iberia around 200 BC, but only targeted shallow ores with silver isotope fractionation, not the deep ores the Phoenicians were able to access.

The low levels of isotope fractionation seen in Phoenician sliver objects from Anatolia and Sardinia suggest that the Phoenicians were using the same deep-mining methods there in the tenth century BC, indicating that these people were more than talented sailors, but skilled workers in other fields, capable of transfering skills from one end of the Mediterranean to the other.

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Deciphering ceramics manufacturing techniques from the medieval city of Qalhât, Oman.

At the beginning of the first millennium AD, the Indian Ocean became a region of long-distance trade between the Middle East, India, South(east)-Asia and Africa, thanks to monsoon winds. The Qalhât site (Sultanate of Oman) located near the Ra’s al-Hadd was a key harbour city for short- to long-distance trade from the 13th to the 15th century. The city was founded around 1100 AD, sacked by the Portuguese in 1508 and becametotally abandoned during the 16th century. More than two hundred thousand ceramic shards have been  excavated from this site, and preliminary visual classifications based on shape and decors, as well Raman and X-ray fluorescence studies have been carried out. Many questions are still open for pottery characterised by a simple monochrome glaze and a porous body intermediate between that of terra cotta and faience. There are two well defined groups by visual examination, the so-called ‘Blue speckled’ and ‘Brown speckled’ wares; these are commonly found in many sites of the Arabic Peninsula and their place of production is highly disputed.

In a paper published in the journal Boletín de la Sociedad Española de Cerámica y Vidrio on 20 July 2020, Liliana Gianni of MONARIS (Molécule aux Nano-Objets : Réactivité, Intéractions et Spectroscopies) at Sorbonne Université, Hélène Renel of the Laboratoire Orient & Méditerranée at Sorbonne Université, Aleksandar Kremenović at the Faculty of Mining and Geology at the University of Belgrade, and Philippe Colomban, also of MONARIS, present the results of a studt which sought to obtain objective information concerning theirplaces of production, local, imported from Iran or elsewhere.

‘Blue speckled’ ware refers to pieces with a medium porous body, generally reddish and a glaze showing a wide variety ofshades of blue or green, sometimes pinkish or purple, or greyish and even nearly black. This glaze is characterised by millimetre dark speckles and is often slightly bumpy. Shapes of pottery are very typical, mostly ranging from wide shallow bowls with a straight lip or, most often, a flange, to jars in part. This ware has been found on the coastal sites of Iran, south Arabia, India and East Africa dating to the 14–16th/17th centuries. It is variously known as ‘Persian Blue speckled’, ‘Monochrome’or ‘Blue monochrome’, and is most commonly given a south Iranian origin, although a south Arabian production is also sometimes considered.

 

‘Blue speckled’ samples and corresponding cross sections for (a) 1; (b) 3; (c) 5; (d) 6 and (e) and (f) 8 shards. Gianni et al. (2020).

‘Brown speckled’ wares include a variety of pieces with arather fine grained, dense body, greyish or light red, sometimes with both colours. The glaze is brown to green, with millimetre dark speckles, showing orange splashes in a greenish matrix when the body has two colours. It is also common on the late sites of the Persian Gulf area and south Arabia, from the 16th century onwards, and is known as ‘Bahlâ’ or ‘Khunj’ wares. Its origin is under debate, whether from the Oman peninsula where similar pieces are still produced Its origin is under debate, whether fromthe Oman peninsula where similar pieces are still produced today, or from south Iran, in the district of Khunj in the Hormuz straights where wasters were seemingly identified in the 1970s. Shards of this type are even sometimes (mis)interpreted as of South Asian origin due to the high quality of the body and are often difficult to distinguish by eye sight but two different groups of shapes may nevertheless be individualised, one including flanged plates similar to the ones of ‘Blue speck-led’ ware, the other one with rather deep bowls with straight pointed lips as in Qalhât, each group possibly testifying a different origin or dating.

 

‘Brown speckled’/green samples and corresponding cross sections for Qa12, Ba21a, Mo20, Sa18.1 and Sa18.2 shards. Gianni et al. (2020).

The technology of these glazed ceramics seems to be among the simplest one: only one type of (clay-rich) earth or a simple mixture of common clay and sand was sufficient. The elemental and Raman analysis allowed the identification of the glaze type. Some phases, stable in contact with the molten glaze and rare from the geological point of view, as well as some minor or trace elements were used as provenance markers. The green body can then be coated with a glaze-precursor slip and put directly in the kiln. This simple technology limits the chance to find specific chrono-technological markers. Firing of terra cotta- and faience-like pottery is generally conducted at a relatively low temperature, between 850°C (apparition of liquid phases activating the sin-tering) and 1150°C (highest temperature achieved by many kilns), sufficient to form a transient liquid phase that will weld quartz and feldspar grains decreasing the porosity but without developing a significant volume of new phases as observed for stoneware and porcelain. Working techniques of traditional potters may have continued using raw materials coming from the same quarries without much change for centuries after the beginning of the exploitation. In this way, comparison with modern and contemporary traditional ceramics can be very informative. Thus, visually similar modern ceramics (19–21st centuries) were collected from Oman sites around Bahlâ which is a well-known pottery production centre, located in inland Oman, about 200 km to the northwest of Qalhât and close to the archaeological site of Salut (around 200 km from Qalhât and 40 km from Bahlâ). The Late Islamic period (i.e. 17th century onwards) Bahlâ wares excavated from Qattara Oasis, close to al Ain city, about 200 km northwest of Bahlâ were recently studied.

In Gianni et al.'s study, a multistep analysis protocol was pursued to obtain comparative information: (i) macrostructure examination of pottery sections and Raman microspectroscopy of glazes and minerals of the body (using the mapping modalities) in association with X-Ray Powder Diffraction, (ii) glaze composition analysed by scanning electron microscope/energy-dispersive X-ray spectroscopy, and (iii) thermal expansion measurements to determine the firing temperature.

Five representative ‘Blue speckled’ and five ‘Brown speckled’ (one from 13th century and 4 post-medieval) shards were selected on the basis of previous work in which different groups were identified: hundreds of shards have been classified according visual criteria, 65 of them being analysed by Raman microspectrometry (including 31 ‘Blue and Brown speckled’ shards), plus respectively 58 of them at the laboratory and 41 other at Qalhat site by portable X-ray fluorescence. Blue shards represent allthe variety of enamels. The good homogeneity of the ‘Brown speckled’ wares observed by archaeologists and previous work led to the selection of a single medieval sample. The selected shards were cut with a saw and the cross sections were observed with an optical microscope. However polishing liquids generate a strong fluorescence, detrimenta lto Raman analysis due to the penetration of chemicals into the porous body. Porosity was evaluated in an area of 6 mm² per sample using ImageJ software. Pore types were classified as a function of their dimension with small (5–50 μm), medium (50–100 μm) and large (over 100 μm) size. The number of pores and percentage of three dimension classes (small, medium and large pores) were calculated to obtain the most characteristic porosity dimension for each sample. The bubble number was calculated in the same area of 6 mm² while the mean thickness was extrapolated along the entire sample section.

identificationFor all samples of the two groups, X-Ray Powder Diffraction patterns showthe presence of three abundant mineral phases: quartz, augite (a pyroxene), and albite (a plagioclase feldspar). Only sample Qa12 contains quartz as the abundant mineral with augiteand albite as moderately to minorly present minerals. Differentiation of the old Qa12 sample is thus obvious. Minor amounts of paragonite (a mica) werre observed in sample 6. Amorphous X-Ray Powder Diffraction patterns are usually obtained for glazes coloured ingreen or blue. However, for sample Ba21, two mineral phases were noticed such as diopside (previously reported for Late Islamic Arabic period productions) and calcite. Mineral phases with minor amounts which were detected by Raman analysis were not detected by X-Ray Powder Diffraction. Furthermore, from X-Ray Powder Diffraction patterns, the content of each mineralphase could be estimated to be less than 5%.

 

X-Ray Powder Diffraction patterns for samples Ba21 (top) and 6 (bottom). Indexed phases of quartz (PDF# 01-089-1961), augite (PDF#01-088-0856), albite (PDF# 01-089-6428) and paragonite 2M1 (PDF# 01-076-5968) are presented in the form of straightintensity lines at the bottom. Gianni et al. (2020).

Previous methodological investigations have demonstrated that Raman mapping could be more efficient than X-ray powder diffraction to identify the minor phases. However, X-Ray Powder Diffraction gives a more realistic view of the major crystalline phases.

waresBody: Samples of ‘Blue speckled’ group look rather similar withtheir red bodies. Examination of the cross sections showed that samples 5 and 8 appear darker (more red) inthe core of the section and lighter towards the two sides, suggesting different firing conditions than the others. The number of pores and their dimensions were calculated by theobservations under the optical microscope and the images taken at low magnification. Considering the number of pores present in the same area, bodies of the samples turn out to be similar with a medium level of porosity (24–58 pores per unit area) with the exception of sample 3 which is more compact; 24 pores were calculated for samples 1 and 8 while samples 5 and 6 Exhibit 58 and 40 pores per surface unit, respectively. The percentage of the pore size in all samples is comparable: around 60% large pores, around 25% medium pores andaround 10% small pores. Sample 5 has a lower percentage (2%) of small pores and sample 3 differs from the others withthe total absence of pores in the area considered. The dimension of the smallest pores is similar whereas some differences in the large pores were found. However, distribution of the pore size is analogous. Thus, macrostructures are very similar, except for sample 3 where the pore size is much smaller indicating a higher firing temperature or the use of finer particles or a composition with more flux. Regarding the body, no specificity can be identified for sample 5 which is assigned to a potential production of Iran on the basis of visual examination.

The most frequent Raman spectrum collected in mapping analysis is assigned to quartz. The presence of dolomite is also confirmedby Raman scattering. The unusual presence of phosphate in almost all the samples is worth mentioning (except for sample 8), with the characteristic phosphorus-oxygen mode peak at about 960 cm⁻¹. This phase may arise from minerals or more likely from ashes of animal residues (dried animal dung) or contamination (soil, ingredients kept in the pottery). Gianni et al. note that fish head and bone residues, likely used as fuel (due to oil-rich content) have been found close to Qahlât kilns. Thus, pottery exhibiting a high level of phosphate such as samples 3 and also Qa12, Ba21, Sa18.1 may have been produced using similar raw materials and/or technology or may have had similar use. Only sample 8 does not exhibit the phosphate signature.Also, in all bodies of ‘Blue speckled’ ware, frequent titaniumoxide polymorphs such as anatase (140 cm⁻¹) and rutile (444 and 605 cm⁻¹) are present, suggesting firing temper-atures below about 1200°C (i.e. under the temperature required for the complete transformation of anatase into rutile from about 900°C for nanometric grains to about 1200°C for coarse grains). Anatase is abundantly present in samples 1, 3, 5 and 6. The rare presence of rutile was detected in samples 3, 5 and 8 (also in Mo20 and Sa18.2; totally absent in Ba21 and Sa18.1.

Hematite and magnetite were found in all the samples (abundant in samples 1, 3 and 8), confirming the use of oxidizing firing atmosphere (as proposed by the observations of different colours between the core and sides of cross sections) while maghemite was detected in samples 3, 5 and 6. Maghemite transforms into hematite by heating above 800°C. Augite was only clearly found in sample 1 (like sample Sa18.1). Albite and microcline arecommonly observed. Calcite and dolomite present in some of the samples propose lower firing temperatures (below 1200°C). Traces of organic molecules (oleic acid) probably resulted from food storage in the vessels were found insample 5.

Glazes ofsamples 3 and 8 show a heterogeneous dispersion of the blue colour. Composition analyses show that copper oxide content ranges between 0.3 (sample 3) and 1.62 percent by weight (sample 5). The tin oxide content is relatively high (1.2–1.9%), in agreement with the possible use of bronze residues (cassiterite was not detected by Raman scattering, thus tin was dissolved within the glaze network and did not opacify). Thiscould be due to the mixing of colourless and coloured glazes (anima/corpo technique) which could be consistent with the importation of the raw materials used for preparation of the glaze (the precursor powder) and the speckle distribution. Some bubbles were found in the glazes of samples 1, 3 and 5, which indicate the reaction with the body, suggesting a single step firing process of an enamelled green body. The number of bubbles for unit area is similar as well as dimensions of the pores for samples 1 and 5 while larger bubble diameters were measured for sample 3 (richer in alumina). No bubbles were observed in the glazes of samples 6 and 8 with ×5 magnification. The thicknesses of glazes are comparable for the top and bottom sides as well as between all the glazes. These technological differences (presence of bubbles, colour dispersion and mono- or multistep firing) may correspond to different productions (place or time?) or even different locations in the kiln, the gradient of temperature being rather big in an ancient kiln. The highest copper oxide contentof the glaze of sample 5 explains the darker colour but no other significant differences were found regarding the body. The composition of all glazes is very similar, except the alumina concentration of sample 3 which is a little higher. Also, the variable content of potassium, which Gianni et al. note is an important criterion, (potassium oxide forms 2.65% by weight of the total oxide content in sample 3, for example, 5.18% in sample 5, 3.5% in sample 6, and 5.75% in sample 8). However, this isnot associated to a high level of magnesium (magnesium forms less than 0.6% by weight of the total oxides in samples 1, 5, 6, and 8, and between 2.2 and 2.3 in sample 3), which could suggest the use of ashes as flux. The equal con-centration of titanium (titanium oxide forms between 0.3 and 0.6% by weight of total oxides in all samples) causes Gianni et al. to suppose the same type of sand as well as the comparable concentrations of barium (barium oxide makes up 0.3% by weight of the total oxides in samples 1, 5, and 8, and between 0.5 and 0.7% by weight in samples 3 and 6). The glazes also containa small amount of lead oxide (which forms 1-2% by weight of the total oxides in samples 1, 3, and 8, and 2.5% in samples 5 and 6), tin oxide (roughly 1.8% by weight in all samples), copper oxide (less than 0.4% by weight in all samples except sample 5, where it comprised 1.6% by weight). Gianni et al. also mention that cobalt was not detected in the glazes, the turquoise colour being only due to copper ions. There are no arguments to discriminate sample 5 from the others and it can be concluded that all glazes are identical with a single origin of production.

 

Comparison of the glaze compositions of ‘Brown speckled’ (a), (b) and ‘Blue speckled’ wares (c), (d); (a) and (c): refractory oxide content vs. flux, (b) and (d): flux composition. Gianni et al. (2020).

All samples havethe same Raman broad spectrum with the vibrational mode at about 510 cm−1and the stretching mode at 1090 cm⁻¹, a signature assigned to alkali glass (sodium oxide + potassium oxide (+ calcium oxide) flux). The intensity of the roughly 960 cm⁻¹ broad component, characteristic of poorly polymerised silicate network is consistent with a moderate firing temperature. In sample 5, the characteristic resonance Raman feature of the so-called amber iron sulphite chromophore at about 420 cm⁻¹ explains the strong darkening of the blue hue. The glaze structure is also different. The lack ofthe 960 cm⁻¹component and the shift to 1100 cm⁻¹ of the silcon oxide stretching mode indicate a different composition, as also confirmed by the highest silica and alumina contents measured by Scanning Electron Microscopy with Energy Dispersive X-Ray Analysis. There are no differences between blue and grey glazes because only the glass signature was detected in the Raman signature implying that the colouring copper ions were dissolved in the glaze network.

 

Representative Raman spectra recorded on sample glazes: (a) ‘Brown speckled’, (b) ‘Blue speckled’ wares. Gianni et al. (2020).

In the cross sections of the ‘Brown speckled’ ware samples, a similarity was observed between Qa12 and Sa18.1 as well as Ba21 and Mo20.The grey core of the body develops a darker red layer towards the two opposite sides of the shards, suggesting oxidising firing atmosphere.

The red body of sample Sa18.2 shows a typical black core indicating the use of a clay rich in humic acids (such clays exhibit a better plasticity). Pore dimensions, number and percentage of small, medium and large pores were calculated as for ‘Blue speckled’ samples. The higher porosity levels measured for the modern samples Ba21 and Mo20 are consistent with a two-step firing process (glaze deposited on an already fired put porous body) while the matrix of the ancientsample Qa12 appears compact without any pores under the used magnification in the area analysed. Usually, the heating rates used in ancient times are much lower than those presently used, which could lead to better sintering for a similar firing temperature and smaller bubble size due to the higher viscosity of the glaze. Samples Ba21 and Mo20 display about 150 pores for the area analysed of comparable dimensions (Ba21: 51–128 μm; Mo20: 35–250 μm) taking into accountthat the range includes the smallest and the biggest pore found in the area. Intermediate porosity levels were calculated for the two shards of Salut samples (Sa18.1 and Sa18.2) respectively with 125 and 80 pores for the area analysed. Samples Sa18.1 and Sa18.2 appear similar with the presence of small, medium or large pores while Ba21 is exclusively characterised by large pores.

Feldspars such as albite and microcline were detected in all the samplesby Raman analysis, except samples Qa12 and Mo20. Microcline was also found in samples Ba21 and Sa18.1, Sa18.2 while albite signal is absent only in sample Qa12. Consequently, thesand used for samples Ba21, Sa18.1 and Sa18.2 is differentfrom that used for samples Qa12 and Mo20. It is probable that no sand was specifically added for Qalhât shard Qa12. Thus, different raw materials have been used for these shards. Calcium phosphate was abundantly found inall the samples while it is scarcely present in samples Mo20 and Sa18.2. In fact, phosphate is rarely found in pottery body and this appears as a common characteristic common with ‘Blue speckled’ wares. Rutile and anatase were also abundantlyfound in samples Qa12 and Sa18.2 and scarcely in sample Mo20.

Iron oxide is present in the form of hematite, magnetite and maghemite. Magnetite and maghemite are absent in sample Sa18.1 and the latter was also not found in sample Ba21. The presence of hematite in all samples is consistent with an oxidising atmosphere during firing. A major presence of augite was clearly found only in sample Sa18.1 by Raman analysis, although augite was detected by X-Ray Powder Diffraction in all samples. This demonstrated that one technique may not be sufficient to detect all the phases present. Augite is a type of pyroxene usually found in specific rocks such as ophiolites, lavas and gabbro. Ophiolites are common in Oman Mountains and detection of augite could be a reliable marker of local production. Iranian geology also incorporates ophiolite and augite, but far away from Hormuz Detroit. Calcite is absent in samples Qa12 and Sa18.2 while dolomite was only detected in sample Sa18.1. 

All the samples selected are covered by a glaze layer with colours of brown (Qa12 and Sa18.1), green (Ba21 and Mo20) and yellow-brown (Sa18.2) and similar thickness (about 150 μm). Samples Qa12, Ba21 and Sa18.1 have glazes on both sides. Observation of the cross sections showed the similarity of samples Qa12 and Sa18.1 (no significant inter-phase between the body and the glaze) and also some similarity with sample Sa18.2. An intermediate layer of aboout 80 μm between the upper glaze layer and the paste can be distinguished for samples Ba21, Mo20 and Sa18.2. Such an interlayer could result from a deposit (engobe?) or from a reaction zone due to a deposit of the enamel slurry on a green body and a single step cofiring process that promotes the extent of the reaction zone. No bubbles were found in any glazes, indicating a low viscosity at the firing temperature and a deposition on already prefired body.

The elemental analysis shows two groups. On one hand, samples Ba21, Mo20 and Sa18.1 (very close in the values of refractory oxide content vs. flux) are coated with analkali-containing glaze and on the other hand, samples Qa12 and Sa18.2 are glazed with a lead-based composition (more widespread in the graph than the others). Each value is the mean of data measured on three spots. The concentration of lead in the latter two samples is variable and higher than 14% by weight (the others below 4% by weight). This indicates that the glazing technology of sample Sa18.2 is the most comparable tot hat of the mediaeval Qa12 shard. This is consistent with a technological change from lead-rich glaze for medieval and post-medieval periods to an alkali-rich glaze for the modern period. As usual, lead-based copper-containing glaze is green. The high level of iron oxide measured for Qa12, Sa18.1 and Sa18.2 glazes explains the brown colour.

Raman sig-natures show the characteristic silicone oxide bending and stretching broad modes of poorly polymerized amorphous silicates, i.e. glassy silicates with relatively low temperature of melting. Due to the incomplete reaction between the raw materials used to prepare the glaze, signatures of quartz and feldspars were recorded in many places. For instance, in sample Mo20, the contribution of unreacted quartz and feldspar grains is shown, hindering the observation of the glaze signature (broad components). It should be noted that the size of the probed volume by the Raman microspectrometer (roughly 5 μm × 5 μm × 15 μm) is much smaller than the glaze thickness, which guarantees the lack of contamination by the signature of body phases and the possibility to identify the glaze heterogeneity. Raman spectra of Qa12 and Sa18.2glazes are similar, without features at about 750 cm⁻¹, according to a significant lead content, in agreement with the glaze composition.

Additional iron oxide signature with spinel structure, likely magnetite was found in Ba21 and Sa18.1 glazes, which indicates firing under reducing atmosphere or the use of a clay rich in humic acids. The green colour of samples Ba21 and Mo20 is however not only related to a high level of copper. The colouration is likely due to the combination of iron⁺² and iron⁺³ ions, but clear observation of the Raman signature of spinel could indicate the presence of ions promoting the spinel structure such as chromium. The very surprising high level of barium oxide (about 12% by weight) detected in Ba21 glaze is interesting. The narrow 667 cm⁻¹ peak indicates traces of calcium-antimony oxide opacifier. 

The analysed samples obviously belong to different productions. Samples Sa18.2 and Qa12 are very different from the others, both regarding the body and especially the lead-rich glaze. On the other hand, the glaze of other shards is alkali-rich and this can be interpreted as a technological change between the medieval/post medieval and modern period.

Thermal expansion analysis was pursued to make the precise estimation of the firing temperatures. Thermal expansion measurement has been one of the favourite techniquesto control ceramic production and qualify raw materials and glazes. The onset of the thermal expansion jump is considered at the firing temperature.

 

Thermal expansion curves measured on sample bodies: top, ‘Blue speckled’wares, bottom, ‘Brown speckled’. Gianni et al. (2020).

The curves obtained indicate that the ‘Blue speckled’ ware ceramics were fired around 1140°C for samples 6 and 8 and at a little higher temperature, 1150°C for the others. The closer values may clearly indicate the same type of kiln. In accordance with the identification of glaze compositions and phases, thermal expansion curves confirm the homogeneity of the group. Sample 5, with dark glaze coloured both by copper ions and iron sulphite amber chromophore shows small events at about 300–500°C which were not detected in the other samples (traces of cristobalite?)

Thermal expansion analysis shows the firing temperature ranges for ‘Brown speckled’ ware from about 1080°C for sample Sa18.2 to 1120–1150°C for other samples. Ancient sample (Qa12) was fired at 1120°C. The firing temperatures are fully consistent with the number of pores measured per unit area, the lowest number for the lowest firing temperature and the highest number for the highest firing temperature, except for sample Qa12. Thermal expansion curve of sample Qa12 exhibits a strong event at about 600°C which is characteristic of the α to β-quartz transition, according to the large amount of quartz in the body, i.e. consistent with the use of coarse sand and/or raw earth, without specific preparation. This finding also demonstrates that more recent pottery samples are different from the 13th century ones.

Representative archaeological shards excavated at Qalhât and collected at the important active neighbouring site of Bahlâ were analysed and compared to modern pottery produced in a regional pottery production centre. Augite was detected in allthe shards by Energy Dispersive X-Ray Analysis and in some of them by Raman. Local production of pottery with body having a high content of augiteis thus very likely but more information on the geology of the Oman Sultanate and Iran is needed. Identification of phosphate in almost all the samples (except sample 8) suggests the same procedure of firing, the use of phosphate-containing raw materials or water, or the same type of contamination in relation with the use as vessel or the conservation in the soil. Recording of the oil signature by Raman scattering in someshards is consistent with contamination and a further chromatographic study of the soluble food residues to be extractedfrom the pottery body would be interesting to identify the organic matter and document the function of the utensils.

Elemental compositions of the ‘Blue speckled’ glazes are more or less similar with some differences only found in sample 3 (higher level of alumina) and sample 5 (the amber iron sulphite chromophore darkens the turquoise colour obtained by copper ions according the higher copper oxide and iron oxide content).Considering the different characteristics, the shards appear very similar and may have the same local origin of production. Many other common minerals were found such as anatase (the firing temperature below 1200°C) and rutile (high temperature polymorph, consistent with a firing temperature close to 1150°C) in samples 1, 3, 5, 6 and 8. Whatever the very homogeneity of the bodies at visual examination, specific characteristics can also be identified such as the presence of unreacted feldspar and other particular minerals (e.g.dolomite). The main differentiation can be made by considering the glaze. Importation of the glaze (or glaze precursor(s) only) is possible, the high similarity of the glazes contrasting with the variation of characteristics regarding the body.

Considering the ‘Brown speckled’ glazes, cross sections of samples Qa12 (medieval) and Sa18.1 (absence of an interface, consistent with single step firing) and Ba21, Mo20 and Sa18.2 (presence of an interface, prefiring of body before enamelling?) have different characteristics while the glaze thickness is comparable. Elemental and Raman analysesid entified samples Mo20 and Ba21 as alkali glazed (Ba21, barium-based glaze), as in the case of ‘Blue speckled’ glazes. However, samples Qa12 and Sa18.2 are covered by mixed lead-rich glazes. Feldspar-containing sand appears typical of Bahlâ productions. On the contrary, rather high levels of rutile and anatase are characteristics of Qalhât samples. Important similarity was remarked in compositional and technological aspects between the medieval Qalhât shard (Qa12) and samples from the ruined village near Salut (in particular Sa18.2), with the use of similar technological procedures (lead-rich glaze, single firing in similar kilns) which fit with a slightly lower temperature of firing. The other modern samples (Mo20 and Ba21) belong to another technological procedure (multi-firing?); this can be interpreted as a technological change between the medieval/post medieval and modern period. Sample Ba21 is characterised with its very special specialbarium-based glaze. Finally, Qalhât sample Qa12 and Salut sample Sa 18.2 are glazed with lead-rich glazes whereas alkaline glazes are used for the others. In conclusion, modern Bahlâ pottery cannot be considered as a continuation of Qalhât production (stopped around 1508 with the destruction of the city).

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