In pinning down the final footnotes of that paper, I’ve found myself on one of those dead-end trails that happen when people don’t cite properly. Let me vent some ire.
On page 68 of her Història de la Moneda dels Comtats Catalans (Barcelona 1999), Anna Balaguer writes about the evidence that the count of Barcelona, Ramon Borrell, reformed the coinage of the county in about 1000. Crucial to her argument is a charter that, she claims, indicates by an equivalence that the coin then minted, the diner (pictured above), weighed about 0·37 grams. She gives no text, but cites the previous grand work of the field, Joaquim Botet i Sisó’s Les Monedes Catalanes (Barcelona 1908-10), Vol. I p. 31.
So I find Botet, because I work in a place that has it. And Botet in his turn gave no text, but merely a reference to Josef Salat’s Tratado de las monedas labradas en el principado de Cataluña con instrumentos justificativos (Barcelona 1818), Vol. I p. 90.
So I find Salat, because again Philip Grierson had a copy. And on p. 90, indeed, lo, some text; Salat wrote that the document in question was a sale to Santa Cecília de Montserrat by Llobet and his wife Riquilda, on the 1st of January 1000, of lands at Ortons in Gelida, “por precio de un manchoso del valor de 6 sueldos”, although unfortunately he didn’t give the actual text. He did at least give a shelfmark for the original.
This is only so useful, however, because since Salat’s time, most of the original documents from the abbey of Montserrat have been lost, and we’re reliant on eighteenth-century regesta for them. Nonetheless, what there is has been edited, so I go out and find Francisco Xavier Altés i Aguiló’s “Diplomatari de Santa Cecília de Montserrat II, anys 1000-1077” in Studia Monastica Vol. 37 (Montserrat 1995), pp. 301-394, to look it up.
There is no document exactly as Salat described in the edition. What there is, copied from a source with the same shelfmark as Salat gave, is a document of 31 January 1000, so II Kal. Feb. rather than I Kal. Jan., an odd error to make. It is only given as a summary even of the regesta by Altés, which is annoying, but it was a sale to the same monastery of lands in Gelida by the same people, for a price of “I manchoso in rem valentem et solidos VI”. Which is not the same thing, but one can see how in a bad copy, where the “in rem” and “et” could be missed, a hopeful reader might think it was.
All the same, Salat gave more detail than Altés does, and it is more than possible that Llobet and Riquilda made two sales in the same month, at which rate they could even have been copied up on the same sheet of the same cartulary, being clearly associated. So the possibilities are:
- Salat was faithful to his text, and there were two sales, of which one read as he suggests and one read as Altés reports it; Botet was and Balaguer is correct;
- Salat was faithful to his text, but that text was a bad copy of the document of which Altés gives us the summary; Salat therefore was wrong, and so therefore were Botet and is Balaguer;
- Salat misread his text, which should actually be read as Altés gives it, and his interpretation has no foundation; Botet was wrong and so is Balaguer, and if there weren’t other evidence for two different weights of coin in circulation by the 1010s, the whole thing might come falling down.
The only way to find out what’s what is (a) to wait for the Barcelona volumes of Catalunya Carolíngia to come out and hope that the editors have either solved this or found the missing document’s regestum, or (b) to go to Barcelona and hunt through the volume it should be in, only still not to know, should it not be there, which of our options is correct.
If Botet had checked Salat’s surprising citation in the early 1900s, before the monastery archive was lost; if Balaguer had checked Botet and realised the text was by now dodgy (or if she had just cited Salat, given that Botet gave no detail at all; I presume that she didn’t follow it back)—or if anyone had at any point in the chain given an actual quote—we might actually know whether that particular mancus was worth six diners or not. But since the fact that it’s even stated, if it was, makes it look likely that there was something weird about the coin, I would still argue with it. Unfortunately I rather needed that theory to be sustainable. Oh well.
A Corner of Tenth-Century Europe 
As an archaeologist, allow me to suggest the obvious solution to that problem:
Take a pair of scales and weigh the coins.
Alternatively, write a kind email to somebody at a museum or collection in possesion of said coins and ask them to do the same. Easy-peasy.
A fair point, as far as it goes. The Fitzwilliam’s collection doesn’t have quite that level of Catalan ephemera in it, but the museum in Catalonia whose pages I borrowed that diner image from have enough of it. In fact, I have the weights from find reports anyway, which is how I know that it’s a plausible equivalence.
The thing is that the simple weights aren’t really enough. To make it meaningful we need specific gravity of both coins, and then since a mancus is a gold coin and a diner supposedly silver, we could actually get an idea of what bullion value was at the time. That won’t tell us what people at the time who weren’t melting these things down were willing to give you for a gold mancus, though, which that document might have done if only it said what Salat thought it did.
Part of the point of the paper was that actually, people were melting mancuses down a lot. When payments are made in gold in Barcelona charters from around 1000, it’s almost always “mancusos de auro chocto“, that is, mancuses of cooked gold, suggesting that they’ve been melted down because the users don’t trust the Islamic coins to be worth their weight. This is why I think it wouldn’t be very helpful even if Salat had been right; it would only tell us that this mancus was worth 6 diners. And by the sound of it that mancus wasn’t a coin any more, but some melted gold that was worth that much.
The basic problem is that the coin I pictured is one of three from about a century of Catalan history, and its dating and attribution are uncertain, so even once we know what it weighs, we don’t know what that means…