Monthly Archives: July 2019

Many many Barber Institute coins now online

Following up on that previous post more quickly than usual, the mention of Dr Maria Vrij of the Barber Institute of Fine Arts, my honourable successor and exceeder in post there as Curator of Coins, and also the use of the University of Birmingham’s online objects catalogue to instance a Barber coin, both lead me together to pointing something out that’s deserved notice since it began in March 2016 with some of the Barber’s Roman Republican coinage, which is: they have managed to put really quite a lot more of their coin collection online since I left you know!

An anonymous bronze quadrans of the Roman Republic, struck at Rome in 215-212 BC, Barber Institute of Fine Arts B0073

For a while Maria was keeping me posted as uploads went up, so that I could post about them here, but since I wasn’t really posting and she soon had a new exhibition to cope with, that stopped and I’ve only just got as far as the first stub I made to mention this to you all. What this means is that the phenomenon has meanwhile achieved very serious proportions! When I took on that collection, 188 items were online, out of a collection of nearly 16,000; by the time I left, not least due to the efforts of Maria, that was 462. But since I left, in four fairly short years (three only 365 days each, I believe!), that total has risen to more than the 3,000 items the search will find at once, even in just Byzantine coins. I can determine that it includes 2,109 Roman coins, including 400-odd Republican pieces, but not including 22 Late Roman pieces of about 250, so that at least is still ongoing work, and the Byzantine collection doesn’t yet include the coins of Constantine XI so can’t be finished yet either, but it’s amazing what has been achieved. That achievement includes the digitisation and getting online of 908 Sasanian Persian coins, a larger collection than most other places in the world and surely pretty much the only one online; it includes the fascinating Mardin hoard, which is very worn Roman and Byzantine coins that were some of them countermarked for use in the medieval Islamic world and therefore presumably were all used thus, since they were buried together; and a selection of Trebizond and Vandal stuff, to name but a few things I can find in searches.1

An anonymous copper-alloy follis struck in the Byzantine Empire between 976 and 1035 and then later countermarked 'Saif' and lost as part of Mardin Hoard, Barber Institute MH0099

An anonymous copper-alloy follis struck in the Byzantine Empire between 976 and 1035 and then later countermarked ‘Saif’ and lost as part of Mardin Hoard, Barber Institute MH0099

So great things have been afoot, and so many feet have they been a’ that I can’t actually determine how great they are; but we are talking records in the thousands, all with good images and metadata that tell you at least something about the rulers who issued them and sometimes the collectors who found them and made it possible for the Barber to make them available all these years later. More is doubtless still to come, but meanwhile I invite you to have a browse, follow some cross-references and revel in the numismatic riches of it all!

A gold hyperperon of Emperor John III Vatatzes of Nicaea struck at Nicaea in 1227-1254, Barber Institute of Fine Arts B6081

A gold hyperperon of Emperor John III Vatatzes of Nicaea struck at Nicaea in 1227-1254, Barber Institute of Fine Arts B6081. Note the way that the method of striking with two dies has left the image of Christ doubled up on the obverse!

1. The Mardin Hoard has actually been exciting people for long enough to be published in print, at least in summary, as N. M. Lowick, S. Bendall & P. D. Whitting, The Mardin Hoard: Islamic countermarks on Byzantine folles (London 1977).

All that Glitters 7: the slight return

With due respect thus paid to events that have overtaken us, I return to my sort-of-scheduled programming here at A Corner of Tenth-Century Europe and also to the subject of Byzantine coinage, from which it seems I will probably never entirely escape. And why indeed would one want to? But I can bring one thing to a close with this post, which is my reports on the experiments that my collaborators and I did on the All That Glitters project analysing Byzantine gold coins by X-ray Fluorescence of which you have by now heard so much, at least until we actually publish properly on it. So here is the last post on the theme for the time being.1

Bruker S8 TIGER XRF analyser open for business

And therefore last chance to re-use this photograph of the S8TIGER WD-XRF machine in the Department of Chemistry at the University of Birmingham!

I’ve done so many of these posts now that summarising the experiments in any detail would be quite difficult as well as tedious, so for the purposes of this post, let’s just say, we’d gone into the project hoping to say something about changes in the trace elements present in the coins that might tell us something about changing metal sources and minting practices, and we’d found that for two reasons that wasn’t really possible, although we did still find some stuff out doing it. The first and more historical of those reasons why not was simply the nature of the Byzantine tax system, which persistently called in coins from across the Empire, melted them down and redistributed their metal centrally to the mints for striking, thus ineluctably mixing all the different mints’ practices together; the only place we could really see compositional difference was provinces that were falling off the Empire, and even then interaction was usually sufficient to keep things mixed up. But the other reason was that the detection machinery, be it never so sophisticated, couldn’t really tell us what we wanted to know, and that also for two reasons, one being because of invisible surface deposits from the soil that we couldn’t properly see through with the X-rays (and couldn’t safely remove very effectively), and the other being simple and frustrating variation in results.

At what had been supposed to be the end of the project, therefore, because of the various constraints and inefficiencies of getting the coins safely to the analysis machinery and back, we had unspent money left in our grant budget, and so I thought—I think this was me, but if not, I’m sorry to either Rebecca Darley or Maria Vrij for stealing their credit here—that one useful thing we could do with half a day was get some kind of baseline figure for how bad that variability was. So on 16th February 2016 we did a very simple experiment. We took one coin, put it in a sample cup and then without touching it, moving it or changing it in any way beyond what the automatic handling in the spectrometer put it through, ran it through exactly the same test five times, and then turned it over in the cup and did that again for the reverse side, giving us ten runs on the same object in which there was literally nothing more that we could have done to reduce variation.

Apparently I wasn’t taking the security photographs that day, so I cannot show you that coin in its sample cup, but here it is in shiny catalogue image; it is a gold-ish tremissis of Emperors Leo III and Constantine V probably struck in Sicily or Italy, as we demonstrated in the last one of these posts, between 717 and 741, Barber Institute of Fine Arts B4542

The results were not encouraging. Admittedly, in terms of gold content they were not too far apart, ranging from 85.26% to 87.21%, an error margin of only about 3%, but even that is 2% raw difference in apparent metal content. People have founded theories about currency alteration on the basis of disparities like that, so if you’re getting them between measurements of a single coin that’s a problem. But the less present elements had similar amounts of variation: silver 7.63% to 8.84%, copper 1.78% to 2.39%, iron 0.15% to 1.04%, aluminium 0.38% to 0.67%, magnesium 0.13% to 0.67%, and then a host of other elements that one didn’t even see in some or most tests. Again, these margins may not seem like a lot, less than a per cent in some cases, but those less-than-per-cent margins are in some cases more than the total percentage of a metal in question, which meant that the error margins we were seeing were mathematically huge, in the order of 300% to 500%. Basically, no respectable scientist would trust such figures, because they could have no confidence that they would be able to reproduce them, and fair enough, because here we were trying to do so and more or less failing.

So what did all this tell us? One gloomy conclusion, that for all we’d hoped to find differently, XRF probably still isn’t a workable way of analysing trace elements in coins, we had more or less already reached, but this let us actually put numbers on why not, which is worth something. I’ve since looked at quite a lot of papers using XRF analyses on coins, and I’ve found only one that used an average of several experiments as their working figure, and that was from 1983 (and was by none other than the late lamented Michael Metcalf, and he was dealing with variations of over 20% depending on what he’d done to Philip Grierson’s coins to get those results, which we know because he actually said so in his write-up).2 He wasn’t even a metallurgist! And he presumably also wasn’t paying for machine time, which is the basic reason that I guess people don’t otherwise do this. But it is, one might say, a little embarrassing for the subdiscipline. Still, I’m not sure that even an average figure from our tests would be very safe to use. How many tests would one need to run on each object to make safe a 300% error margin? What if one of those tests increased that margin? In general, I think that even the best XRF machinery we can get just can’t give accurate figures for small-percentage composition elements, even if it probably still has some application for the big-ticket components. It’s not the conclusion we’d aimed for but when we can get anyone to publish such a negative finding it may not be without value.3 And thus endeth, for now, the sequence.

1. Of course, we have actually published on the project a tiny bit, in the form of Rebecca Darley, “All that glitters…: the Byzantine gold solidus, c. 300-1092″, in Maria Caccamo Caltabiano (ed.), XV International Numismatic Congress, Taormina 2015: Proceedings (Rome 2017), II, pp. 982-985, but that was actually written and given before we’d done these final experiments.

2. That being D. M. Metcalf, “Interpreting the Alloy of the Merovingian Silver Coinage” in C. N. L. Brooke, B. H. I. H. Stewart, J. G. Pollard and T. R. Volk (eds), Studies in Numismatic Method Presented to Philip Grierson (Cambridge, 1983), pp. 113–126, out of 16 studies I know of from 1966 to 2019; I’m sure there are more, though, and if you feel I’ve missed an important one it would be really useful to know!

3. The main reason that we haven’t yet done more on publication of these experiments, even three years down the line, I should explain, is professional mobility. Even in the course of the project, every single project member changed jobs and only two of them even stayed within the same company/institution. Since then several more of us have moved again. Of course, our new employers all hired us for our own individual qualities and while some of them might like us to do this kind of collaborative inter-disciplinary research, they would prefer to have been part of it, so that only those of us who remain in Birmingham have any immediate professional interest in making this part of our workload. We will publish something on it, because we spent money on the assurance that we would, but it will be when one of us needs it more than whatever else we’re supposed to be working on, and the path to that isn’t yet clear.

In memory of Simon Bendall

I’m sorry as ever for a lapse in posting. Firstly I went on actual holiday, without a laptop—some day there will be pictures, because I did take a camera—and then as soon as I was back I had feverishly to read a 723-page thesis so as to be able to help examine it the following week in Barcelona, in whose airport indeed I now write this post. I had hoped to have written you something about Byzantine coinage by this time as well, and so, I suppose, I am about to do, but it’s not the thing I had hoped for and it must come first, as is unfortunately now common on this blog, because somebody died, and that somebody was Simon Bendall, Byzantine numismatist extraordinaire, whom I knew a little and so want to commemorate here. He died on 26 June after what was apparently a long illness, at the age of 82.

Simon Bendall (1937-2019)

I’m not sure when I first heard of Simon Bendall; it’s possible that it was in citation as I read frantically to prepare for the interview that got me the job managing the coin collection at the Barber Institute. However, I heard from him very shortly after I got that job, because his ever-active networks had brought him the news of régime change and he wanted to ask me for some images for a book he was then working on, which became his Introduction to the Coinage of Trebizond, of which he later kindly gave me a copy.1 That was an illustrative exchange for several reasons, which all help give a sense of the man, so I’ll tell them.

Firstly, I managed almost without effort to enlist him in checking over the Barber’s own initial catalogue of coins of that Byzantine splinter state, because he had once been going to catalogue them for us anyway and had been frustrated at never finding out what we actually had; as a result, to go online at some future point, there is a marked-up printout of the catalogue in the Curator’s work pile, I imagine, where I sadly had to leave it when I demitted. Secondly, yes, print-out, because Simon didn’t use e-mail, and barely used computers; the only practical way to send him a PDF was in print, and all the correspondence I had with him was actual letters, answered in longhand and in scrupulous detail in rather shorter time than I tend to manage with e-mail. Thirdly, that correspondence also got me several stories about one of my predecessors as Curator, the learned but sometimes difficult Michael Hendy, which I was later able to verify from the coin catalogue, because Simon, in his position at the coin dealer Baldwin’s, had been responsible for choosing and sending several important parts of the Byzantine collection while it was under Hendy’s care. Fourthly, it gave me vital ammunition to get the Barber to rethink its image pricing, based on full-size paintings and not really applicable to coins, that when I told him what we would have to charge him he gently pointed out that for that price he could buy an actual one of the relevant coins and photograph it himself for less money. From all this, I got the impression of a man who was a quantity, if you see what I mean.

Before long I was encountering this quantity in print, as well, because Simon was one of the people who had written about the concave fabric of later Byzantine coins, and one of the very few who had asked the important question: well, how did they do it?2 And by then I was also aware that for the coinage of the last and longest-lasting dynasty of Byzantine emperors, the Palaeologans, the standard reference was by one Simon Bendall…3 And in fact, I now learn, a full bibliography of his work would have two-hundred-plus things in it, from two- or three-page notes in the little auction house periodicals we used to have to full-length monographs, because he just knew a lot, largely through his ongoing connections with those same auction houses as employee and then consultant expert. Numismatics is one of the last fields where you don’t have to be an academic to be a major contributor, and that is not least because of the demonstrable importance of the work of people like Simon.

I think I finally met Simon at the International Numismatic Congress in Taormina in 2015, and then again at a couple of meetings of the Royal Numismatic Society. Somewhere in there I must have been told the single event that got Simon onto the web other than his publications, which was the theft of his coin collection in February 2018, sadly not the only retired collector’s collection to get taken from their home that I can think of. Typically, he took it phlegmatically—I suppose he must already have been ill, because he said to me that at least it had saved him the pain of disposing of it. He had once hoped to give it to a museum, he explained, but since it had all been acquired in trade, no UK museum would now touch it; though the thieves had obviously deprived him of one of his life’s works, it did at least mean the collection had not had to be broken up and auctioned as would otherwise have happened. In another of those conversations, more cheerfully, I learnt that his childhood home (and therefore lifelong) football team, Wolverhampton Wanderers, had sent him a card signed by all the squad after he’d passed some 50-year attendance marker I wish I could now remember. Anyway, as this all suggests, he was a fount of stories, and it’s a considerable sadness that he won’t be amassing and telling any more, quite apart from all the other horrors and misfortunes of mortality. He won’t be at the next RNS party I make it to, and people will miss him. So will Byzantine numismatics in general, indeed, and so probably will Wolverhampton Wanderers, and that’s not a bad combination of mourners to have. I hope he went and remains in peace; goodbye, Simon, it was good to have known you.

1. Simon Bendall, An introduction to the coinage of the Empire of Trebizond (London 2015).

2. Simon Bendall and David Sellwood, “The Method of Striking Scyphate Coins Using Two Obverse Dies In the Light of an Early Thirteenth Century Hoard” in Numismatic Chronicle 7th Series Vol. 18 (London 1978), pp. 93–104, and Simon Bendall, “The Double Striking of Late Byzantine Scyphate Coins” in Celator Vol. 12 (Lancaster PA 1998), pp. 20–23.

3. S. Bendall and P. J. Donald, Later Palaeologan Coinage, 1282-1453 (London 1979).

The intellectual impact of Charlemagne’s coinage

One of the occasional, too occasional I think, debates in numismatics is how much the people who have used coins have understood of what’s put on them by their issuers. I sometimes use this as a teaching point by fishing out a British coin and asking people if they know what’s on it and what any of it means, and although someone does occasionally get it that’s not at all usual. In fact, there is even scholarly literature about how little the British know about their own modern coinage, and I don’t suppose we’re too unusual in this respect.1 But how can we judge this for the late antique and medieval worlds? Information is pretty scant, so it’s always nice to come across a hint in our sources that someone or other noticed the design or significance of the money they were using. And in early February 2016, while I was searching for manuscripts to use in Leeds’s palaeography course, I had such a moment. Observe this!

Sankt Gallen, MS 731, fo. 56r

The opening of the Salic Law in Sankt Gallen, MS 731, fo. 56r

What is this, you ask as you are by now well trained to do, and I respond: it is a page from a big collection of lawcodes that now exists in the monastery of Sankt Gallen in what is now Switzerland, the so-called Wandalgarius manuscript. It contains three texts, the Roman Law of the Visigoths, which is basically a filtered version of the Roman Theodosian Code for use in Visigothic territories, the Salic Law that belonged to some of the Franks, and the Law of the Alemans. Each text has a number of decorated initials in it, and in particular when a line starts with omnis or its derivatives, the Latin word for ‘all’, the illustrator often did the first O as a roundel of some kind. The Salic Law, however, is not in its first version which supposedly goes back to King Clovis of circa 500, but the updated reissue of the time of Charlemagne, and in case this wasn’t clear the illustrator has found a roundel that identifies it using the signifier of Charlemagne that most people would have seen, namely, one of his silver pennies.2

Silver denier of Charlemagne struck at Toulouse between 792 and 812

Silver denier of Charlemagne struck at Toulouse between 792 and 812, image by Classical Numismatic Group, Inc., CC BY-SA 3.0, Link

Admittedly, the illustrator has combined the monogram from the reverse side with the legend from the obverse, but they clearly knew that both were there. I don’t know if that makes the figure holding up the not-to-scale coin the big man himself, but since his coins didn’t (yet) feature a portrait, neither presumably would anyone looking at this have known that either. The monogram, however, meant royal authority so clearly that once Charlemagne’s grandson Charles the Bald revived it, it didn’t fully leave the French coinage for a century or more.3 By his coins shall ye know him, it apparently seemed to our illustrator! And of course that would only work if people understood what that image was. Now, we are looking at a pretty intellectual milieu here, I grant you; wherever this manuscript was made but it’s more information than we usually get on this question in the west, so I’ll take it, and now I give it to you.4

1. I got the two weblinks in that sentence from Cécile Morrisson, “Précis de numismatique byzantine” in eadem, Georg.-D. Schaaf and Jean-Mare Spieser, Byzance et sa monnaie (IVe‒XVe siècle) : Précis de numismatique par C&eacutecile Morrisson suivi du catalogue de la collection Lampart par Georg-D. Schaaf (Paris 2015), pp. 7–104, but my notes don’t seem to record the exact page and I’m not going looking for it right now. More in-depth consideration of the issue has focused on Roman coinage, for which see for example C. H. V. Sutherland, “The Intelligibility of Roman Imperial Coin Types” in Journal of Roman Studies Vol. 49 (London 1959), pp. 46–55.

2. On the Salic Law, there is no easy guide, but T. M. Charles-Edwards, “Law in the Western Kingdoms between the Fifth and the Seventh Century” in Averil Cameron, Bryan Ward-Perkins & Michael Whitby (edd.), Late Antiquity: Empire and Successors, A.D. 425–600, Cambridge Ancient History 14 (Cambridge 2000), pp. 260–287 gives you a reasonably up-to-date account of both this and its fellows. For an account of the difficulties of the attribution of each recension, see Patrick Wormald, “The Laws of the Salian Franks. Translated and with an Introduction by Kathleen Fischer Drew. Philadelphia: University of Pennsylvania press. 1991. ix + 256 pp. £33.20 (£11.94 paperback). ISBN 0 812 21322 X (0 812 28256 6 paperback)” in Early Medieval Europe Vol. 2 (Oxford 1993), pp. 77–79, DOI: 10.1111/j.1468-0254.1993.tb00011.x.

3. Charlemagne’s coinage is discussed in Simon Coupland, “Charlemagne’s Coinage: ideology and economy” in Joanna Story (ed.), Charlemagne: empire and society (Manchester 2005), pp. 211–229, reprinted in Simon Coupland, Carolingian Coinage and the Vikings: Studies on Power and Trade in the 9th Century, Variorum Collected Studies 847 (Aldershot 2007), chapter I.

4. I’m sure I’m not the first person to spot this, and the person I would bet has is Ildar Garipzanov, probably in Ildar H. Garipzanov, “The Image of Authority in Carolingian Coinage: the image of a ruler and Roman imperial tradition” in Early Medieval Europe Vol. 8 (Oxford 1999), pp. 197–218, or idem, The Symbolic Language of Authority in the Carolingian World (c. 751-877), Brill’s Series on the Early Middle Ages 16 (Leiden 2008), but again, alas, I cannot check this right now. Sorry Ildar!

Name in Print XXI: Islands are the New Frontiers

After the drought, apparently, cometh the monsoon. The short delay in posting this caused by the International Medieval Congress just gone has seen me with another publication and I hadn’t even told you about this one yet!

Vol. 31 issue 2 of al-Masāq: Islam and the Medieval Mediterranean, entitled Not the Final Frontier: The World of Early Medieval Islands

Vol. 31 issue 2 of al-Masāq: Islam and the Medieval Mediterranean, entitled Not the Final Frontier: The World of Early Medieval Islands, editors Jonathan Jarrett, Luca Zavagno and Rebecca Darley

What is this, you may ask, and to that I say, it is a special issue of the well-known journal of the Society for the Medieval Mediterranean, al-Masāq: Islam and the Medieval Mediterranean, to wit volume 31 issue 2, which has been edited by Luca Zavagno of Bilkent University, Rebecca Darley of Birkbeck, University of London and also myself. If you cast your reader’s mind back you may remembr me saying Luca and I had got some money to run a program of workshops on Mediterranean islands in the early Middle Ages, on which Luca is preparing a book, a program that somehow turned into a small international conference about which I will eventually report but is already documented here; this issue is the proceedings of that conference.

Cover page of Jonathan Jarrett, "Nests of Pirates: the Balearic Islands and la-Garde-Freinet compared" in al-Masāq: Islam and the Medieval Mediterranean Vol. 31.2, ‘Not the Final Frontier’: The World of Medieval Islands (Abingdon 2019), 196–222, DOI: 10.1080/09503110.2019.1600101

Cover page of Jonathan Jarrett, "Nests of Pirates: the Balearic Islands and la-Garde-Freinet compared" in al-Masāq: Islam and the Medieval Mediterranean Vol. 31.2, ‘Not the Final Frontier’: The World of Medieval Islands (Abingdon 2019), 196–222, DOI: 10.1080/09503110.2019.1600101

Now, I spoke at that conference, setting up a deliberately odd comparison between the Balearic Islands and a coastal, landward space, the century-long Muslim colony at la Garde-Freinet in Provence, so I am in this issue, meaning I have a new article out.1 The basic point is that though you’d think there are some pretty basic defining characteristics of islands, they don’t affect how island spaces work as much as other factors, and as a result a landward space can be just as or more ‘insular’ as a geographic island, depending on other things. When I gave that paper I did so with very little knowledge of the areas concerned; by the time I submitted it I knew rather more; and by the time I’d finished dealing with the reviewers’ comments, I knew quite a lot, including about Malta (which is in there too, now), though not enough to prevent me running into someone on Tuesday who had published on la Garde-Freinet whose work I’d missed.2 Finding that stuff out, as it so often seems to do when I go looking for something, exposed a number of assumptions and flaws in the historiography, so there is definitely scholarship going on here, but the overall point that scholarship is serving is a little quirky. I still think it’s interesting and a good piece, however!

Start page of Luca Zavagno, Jonathan Jarrett and Rebecca Darley, "Editorial" in al-Masāq: Islam and the Medieval Mediterranean Vol. 31.2, ‘Not the Final Frontier’: The World of Medieval Islands (Abingdon 2019), 129–39, DOI: 10.1080/09503110.2019.1596645

Start page of Luca Zavagno, Jonathan Jarrett and Rebecca Darley, "Editorial" in al-Masāq: Islam and the Medieval Mediterranean Vol. 31.2, ‘Not the Final Frontier’: The World of Medieval Islands (Abingdon 2019), 129–39, DOI: 10.1080/09503110.2019.1596645

Now, in fact, because of being an editor, I’m actually in this issue twice, because Luca, Rebecca and I co-wrote the ‘Editorial’.3 Actually, truth be told, Luca wrote it, then we severally interveneed, but it’s basically Luca’s text and ideas, and Luca has read a lot about islands and can synthesize it very thoroughly. Otherwise you can find in this issue a study of Mediterranean sea traffic measured from shipwrecks by diving archaeologist Matthew Harpster of Koç University in Istanbul; Luca’s own thorough comparison of most of the islands of the Mediterranean in their transition from Byzantine to Islamic rule; a painstaking study of Chios, an island in the Ægean made unusual by its cash crop, mastic gum, which can be produced almost nowhere else; and Rebecca’s comparison of two extra-Mediterranean islands, Sokotra and Sri Lanka, to bring out some complications of how concepts of island and frontier interact that you couldn’t get without such exterior comparisons, then reflected back in on what the rest of us were doing.4 It’s all quite clever, if I do say so myself, and you might like to read it!

Statistics, as ever: the ‘Editorial’ went through four drafts but I only dealt with two of them, and was eleven months from submission of final version to print, which is really pretty good though demanded a lot to get it done; and my article went in nine days behind that so is basically the same stats, but went through five drafts as I picked up more information. The publication time lowers my average a bit, and the copy-editors were among the best I’ve ever dealt with, especially given that between us all we probably cite or quote in ten languages. So overall, despite tight timescales and some obscure procedures, this has been a good publication experience and I’m extremely pleased that one of my projects has delivered in such a tangible way.

1. Jonathan Jarrett, “Nests of Pirates: the Balearic Islands and la-Garde-Freinet compared” in al-Masāq: Islam and the Medieval Mediterranean Vol. 31.2, ‘Not the Final Frontier’: The World of Medieval Islands (Abingdon 2019), pp. 196–222, DOI: 10.1080/09503110.2019.1600101.

2. That being Andreas Obenaus, “… Diese haben nämlich die maurischen Piraten verwüstet” in idem, Eugen Pfister & Birgit Tremml (edd.), Schrecken der Händler und Herrscher: Piratengemeinschaften in der Geschichte (Wien 2012), pp. 33-54 at pp. 44-49.

3. Luca Zavagno, Jonathan Jarrett & Rebecca Darley, “Editorial” in al-Masāq: Islam and the Medieval Mediterranean Vol. 31.2, ‘Not the Final Frontier’: The World of Medieval Islands (Abingdon 2019), pp. 129–39, DOI: 10.1080/09503110.2019.1596645.

4. Luca Zavagno, “‘Going to the Extremes’: The Balearics and Cyprus in the Early Medieval Byzantine Insular System’, ibid. pp. 140-157, DOI: 10.1080/09503110.2019.1602375; Matthew Harpster, “Sicily: A Frontier in the Centre of the Sea”, ibid. pp. 158-170, DOI: 10.1080/09503110.2019.1602748; Nikolas Bakirtzis and Xenophon Moniaros, “Mastic Production in Medieval Chios: Economic Flows and Transitions in an Insular Setting”, ibid. pp. 171-195, DOI: 10.1080/09503110.2019.1596647; and Rebecca Darley, “The Island Frontier: Socotra, Sri Lanka and the Shape of Commerce in the Late Antique Western Indian Ocean”, ibid. pp. 223-241, DOI: 10.1080/09503110.2019.1604930.