A Troy pennyweight of 24 Troy grains historically derived from the half of an Islamic pre-existing bullion dirhem of 48 grains. Developing that study of weight standards by a further study of coin weight, Skinner (1967) judged the derivation beyond doubt, after showing the early post reform Arabic dirhem “set the standard for the English Penny Sterling” (i.e. that the 22.5 grain sterling penny is intentionally a half of the 45 grain dirhem), which therefore “had a direct effect upon later English standards”.
Facts concerning the Origin of the Troy Weight Standard – Robert Tye
BNS Research Blog 
You ask: “if anyone still cares about such things?” I do, but I don’t know why. Let us just say that I care about such things because I care about such things. — George Reynolds, Little Elm, TX, USA
Thanks George
I travel in hope, so am disappointed but not surprised to find so little engagement with what I have written in this blog piece.
This is probably my final word here so I will use it put a finger on a specific problem I judge has been caused by BNJ itself. Two elderly scholars, Lyon and Nightingale, clashed in the journal in 2008. Each tried to defend preconceived understandings of the development of English historical weight standards by way of erudite references to the rather opaque and fragmentary statements found within early English official documents. Both were perhaps intimidatingly knowledgable regarding those documents. Neither delved into a broader world view, which had been the norm within all previous generations. Unresolved, it left a state of considerable confusion. As I mentioned, I met amicably with Lyon subsequently, in essence to explain why I judged he had been only half right. I could explain more, but instead will outline why I would call Nightingale totally wrong.
We know very well the systems inherited from the medieval world.
English troy (as represented by our bullion weights) ran:
c. 497.6g = 16oz = 320 pennies = 7,680 Troy grains of c. 0.0648g
Paris/Troyes however was
c. 489.5g = 16 oz = 394 deniers = 9,216 Paris grains of c. 0.0532g
Miskimin took it into his head to claim an underlying system where 489.5 grains represented an original pound, yielding the following completely imaginary system:
c. 489.5g = 16oz = 320 pennies = 7,680 grains of c. 0.0637g
Nightingale defended that imaginary system on the basis that Miskimin had had prominent critics, but none had offered a better alternative. That is surely false. Skinner in 1967 built upon a 300 year old better tradition concerning England. Grierson had established a better tradition regarding French matters in 1965. Both Lyon and Nightingale should have profited from John Munro’s 1998 piece, which ripped Miskimin’s position to shreds, here:
Click to access UT-ECIPA-MUNRO-98-01.pdf
In 1963 Munro was a PhD candidate under Lopez and Miskimin and wrote (of one specimen of the latter’s calculations) “clearly this did not and could not happen” He cites a personal letter dated 12 September 1963, revealing that Miskimin was inspired, in part, to believe that Troy weight came to England from France by reading “The Oxford English Dictionary”.
In 1998 he wrote of his position in 1965 saying “I decided that discretion was the better part of valour and made no mention of this rather painful dispute with both Robert Lopez and Harry Miskimin……..it will be noted that I have delayed publication of these matters until after the recent deaths of both Robert Lopez and Harry Miskimin”
In retrospect Lyon’s 2008 criticism of Nightingale was insufficient, giving the journal as it stands a landmark role in the obfuscation of these matters.
Robert Tye
https://independent.academia.edu/RobertTye
Interesting read – thank you. Didn’t Grierson suggest that the Islamic world was the principal conservator of Roman monetary metrology?
Hello George, Rich
Many thanks for the replies. What Grierson really thought seems to me strangely enigmatic. I am curious to get a citation for the point you make Rich. My own general understanding rests fundamentally on two publications from the 1960’s. Skinner’s 1967 take on Offa and Harun in 793, and Grierson’s explanation of what Charlemagne really did in 793 (“Money and Coinage under Charlemagne” 1965). I judge Skinner explicitly revealed the correct underlying 16:15 relationship connecting English and Islamic metrology. Meanwhile Grierson explicitly revealed the correct 16: 15 relationship underlying English and Carolingian metrology. All I am doing at root is saying all three are connected – by that shared understanding. I met Philip Grierson late in 2005, and my key question for him was, why did he never link his own work to Skinner’s? A charming man, he had wished to take me out for a pizza – but I came too late. We chatted generally for a couple of hours in his room, but he apologised – at 95 he was too old for detailed metrological work. He was moved to a care home days later and died a few weeks after that.
I do not have the 1965 Grierson paper to hand, but I recall he gave a correct weight of Charlemagne’s penny (c. 1.7g) and makes 240 of them c. 408g. He then makes that a coin weight, being 15/16 of Charlemagne’s bullion weight of c. 435g. What he must have known but did not say was that Charlemagne’s penny was half an imperial Roman denarius. Also c. 408g is 15 Roman ounces. And c. 435g is 16 Roman ounces. Why did he not just say that?
Going back to your own point Rich, I judge the crucial matter ought to be – where did the Paris grain come from? The later medieval French pound became 18 Roman ounces, but the grain is the one fixed point, at metrification, that was still inherited from Charlemagne. c. 1.7g/32 = c. 0.0531g. Now in his ‘Abd al-Malik paper Grierson postulated what he called a traditional ancient Syrian carat of c. 0.213g. Mathematically that is four Paris grains. From Germany in 2018 Harald Witthöft gave the explicit view that the Paris grain was intentionally a quarter of that “Syrian” carat. In 2022 told me he “got the understanding from Grierson”. Did he mean he got it mathematically from Grierson’s carat, or that Grierson himself thought the Paris grain was also used in the Islamic system? That I cannot say for sure, hence my question to you. Witthöft was then 92, and he died a few months later. Myself, I am sure both Paris and Troy gains came from Islam, and were both part of one greater system created around 697 AD
Enough numbers for now. If this all sounds complicated, well it is not really. The trick is to ignore the distractions. Sadly Wikipedia on “Troy Weight” never mentions Skinner, and if you google Charlemagne’s weight standards, (and its bot) – they will try divert you attention to Harry Miskimin’s work at Yale. John Munro was Miskimin’s Phd student at Yale around 1962. In 1998 in “A Maze of Medieval Monetary Metrology” John revealed what he had already know for 36 years. Miskimin’s ideas about Charlemagne’s weights were complete nonsense. He had waited until both Cipolla and Miskimin were dead before making the matter public. But John Munro died himself back in 2013.
I think all these problems are now solvable – but involve many trips to the graveyard. I do not recall having an informed and thoughtful discussion on these things since I met with Stewart Lyon, who died soon after, in 2021…….
Ha! Seems I woke up in a gloomy mood this morning
All the Best
Rob
Profile fixed?