Note that PB is actually filmed in Manchester. A local entrepreneur who worked briefly on the set, now has a stall selling sausages called “Porky Blinders”
Heyer uses the terms “monkey”'and “pony” in her books, set in the Regency period, which were meticulously researched. The terms are used by upper class characters. I doubt that Cockneys in 1820 would ever have £25, let alone £500, so I’d go with the Indian origins, not Cockney slang.
I just read that book yesterday! 
BTW, something else the UK minted during the 19th century was “fractional farthing” coins. They were mainly used in some of the colonies, but, yeah, 1/960 of a pound wasn’t small enough in those places, and they minted 1/2, 1/3 and 1/4 farthing coins:
Pre-independence India had a similarly complex system
3 pies = 1 paisa
4 paise = 1 anna
16 annas = 1 rupee
Now it’s just 100 (new) paise = 1 rupee
For a while after the currency was ended, the term “anna” was used as a way of stating fractions or percentages. So “four Anna’s” was a quarter of a rupee so it meant 35 percent of whatever you were talking about.
I assume a typo for 25%. Otherwise can you explain the reasoning?
You’re correct. Typo
I read that story! It was in a school reader, about Grade 6. But I remember it a bit differently; it was a half crown, and there were several kids, and when the adult realized that the boy was going to share it with the other kids, he dropped a second half crown, to ensure everyone would get something.
Back when a dollar or five shillings was a large sum of pocket money, I wonder whether the general aversion to large coins was due to the fear of losing them. Losing a buck back then would have been like losing twenty today. Tiny coins are also easily lost, and the gold dollar was never popular in the U.S.
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The ‘Crown’ was not in general circulation. We had a ten bob note (two crowns) and the half-crown. Coins were weighted so that mixed bags could be counted by weighing. For silver coins, a sixpence was half the weight of a shilling and florins and half-crowns were twice a two and a half times respectively. A crown would have to be as heavy as five shillings which made it inconvenient.
A bit like U.S. silver dollars I imagine. They existed, and you might be able to get them at a bank, but apart from Vegas casinos where they were a sort of expected novelty, they were rarely seen in circulation. Overall the U.S. Mint produced silver dollars from 1783 to 1935 but during that time there were years-long periods when none were minted.
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Crowns were primarily a medium for commemorative coins for major (usually royal) events. They were occasionally made until 1981 (as 25p coins) until the Royal Mint decided that 25p had become kind of a chintzy amount for such purposes and switched to making commemorative £5 coins of the same size.
Some of the outdoor scenes are filmed at the Black Country Living Museum at Dudley.
https://www.bclm.co.uk/about/peaky-blinders/337.htm
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Welcome to the SDMB, RonyChapmen. While we do not have a rule against bumping old threads, we do ask that it only be done to add new information relevant to the original topic, which in this case is English money, not Peaky Blinders.
That said, if you wish to discuss the show further, you’re welcome to start a thread on that topic in our forum called Cafe Society, which is the location here for discussion about the arts.
[Moderating]
Welcome to the SDMB, RonyChapmen. While we do not have a rule against bumping old threads, we do ask that it only be done to add new information relevant to the original topic, which in this case is English money, not Peaky Blinders.
That said, if you wish to discuss the show further, you’re welcome to start a thread on that topic in our forum called Cafe Society, which is the location here for discussion about the arts.
India (and other nearby countries) had (and still have) multipliers:
Lakh = 100,000 (of the basic currency unit)
Crore = 100 Lakh, or 10,000,000 (of the basic currency unit)
They seem to use “crore” for any large number as below:
A random Indian news/financial page: http://newsonair.com/Main-News-Details.aspx?id=387805
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This thread was bumped by a spammer who has since been wished away to the cornfield.
I thought these were just numerals: e.g., lakh = 10[sup]5[/sup] like million = 10[sup]6[/sup]. Therefore naturally applicable to money, but are not individual units like a shilling or a dollar, if that makes sense.
My English friend was telling me about UK money terms. Apparently you can say “one pound fifty” but you can’t use “quid” with 50p. You use “quid” as only whole numbers, but if it’s 5 or 10 you say “a fiver” or “a tenner.”
I distinctly remember a news story at the time Britain converted to decimalization. An Englishwoman committed suicide because she could not understand this newfangled system.