Florin diameters

[david.bordeaux 166]

There seems to be great confusion about the diameter of the UK silver florin between 1893 and 1970.

Some sources, including the Royal Mint shop and the Numista website, indicate a change of diameter in 1937, giving 28.30 mm for 1893-1936 and 28.50 mm for 1937-1970. Other sources give a single (but different!) diameter for all florins between 1893 and 1970: Krause (28.3 mm), Wikipedia (28.5 mm), Peter Davies (28 mm) and Matthew Dickinson (28.5 mm).

Analysis of the coins in my collection refutes the idea of a small increase in diameter in 1937. On the contrary, there is a statistically significant decrease in diameter. I find no evidence for the existence of a florin measuring 28.30 mm of any date.

For 1893 to 1936, the diameters measured range from 28.44 to 28.74 mm. From 1937 to 1970, from 28.36 to 28.57 mm.

Assuming that the Mint measured in inches, my conclusion is that the correct (nominal) diameters for florins are as listed below:

•         Godless 1849: nominal diameter 1.10 in = 27.94 mm (rounded to 28 mm)
•         Gothic 1852-1887: 1.18 in = 29.972 mm (30 mm)
•         Jubilee 1887-1892: 1.16 in = 29.464 mm (29.5 mm)
•         1893-1936: 1.125 in = 28.575 mm (28.6 mm)
•         1937-1970: 1.12 in* = 28.448 mm (28.4 mm)

*Another possibility is that the diameter was “metricated” in 1937 to 28.50 mm

Unfortunately the Coinage Acts give only the weight and fineness of each denomination, and not the diameter.

Any thoughts on this would be gratefully received.

[Peckris 2 2,091]

I'd find a variation in diameter puzzling (and surprising) as coin machines were very sensitive to size and weight. On the other hand, they weren't so sensitive that they wouldn't take a worn coin... so ignore me!

[ozjohn 596]

Made the following measurements with my trusty vernier caliper gage:

1888  29,24 mm.

1887 29,24 mm.

1912 29.25 mm.

1945 28.30 mm.

1927 RAM 28.56 mm.

1924 28.55 mm.

1895 28.35 mm.

Just a small sample. 

* gage or gauge I like US spelling it makes more sense like mold for mould. In any case much US English is older English.

Edited March 13 by ozjohn
typo

[ozjohn 596]

6 hours ago, ozjohn said:

Made the following measurements with my trusty vernier caliper gage:

1888  29,24 mm. 11.3g.

1887 29,24 mm. 11.24g.

1912 29.25 mm.11.28g.

1945 28.30 mm. 11.32g.

1927 RAM 28.56 mm. 11.28g.

1924 28.55 mm.11.28g.

1895 28.35 mm.11.25g.

Just a small sample. 

* gage or gauge I like US spelling it makes more sense like mold for mould. In any case much US English is older English.

I should have weighed them as well.

[VickySilver 804]

Good pickup and always happy to see continued interest in the silver coinages! Diameters, sad to say, had escaped my notice other than the "Godless" florin did appear a bit smaller...

[DaveG38 401]

It strikes me that the difference between some of these e.g. 29.24 and 29.25 is just the end result of the limit of tolerances in the strking process. 0.01 of a mm is scarcely visible it seems to me.

[blakeyboy 1,639]

18 hours ago, ozjohn said:

Made the following measurements with my trusty vernier caliper gage:

1888  29,24 mm.

1887 29,24 mm.

1912 29.25 mm.

1945 28.30 mm.

1927 RAM 28.56 mm.

1924 28.55 mm.

1895 28.35 mm.

Just a small sample. 

* gage or gauge I like US spelling it makes more sense like mold for mould. In any case much US English is older English.

..but then you lose the understanding of the etymology and derivation of a word which I think is a shame.

Mr.Webster can take the blame for this- immigrants couldn't learn English quickly so they simplified it.

At least in the US or the UK we don't have to explain to foreigners why we think windows are feminine.....

 

[Peckris 2 2,091]

4 hours ago, blakeyboy said:

At least in the US or the UK we don't have to explain to foreigners why we think windows are feminine.....

We just defenestrate them...

[ozjohn 596]

5 hours ago, blakeyboy said:

..but then you lose the understanding of the etymology and derivation of a word which I think is a shame.

Mr.Webster can take the blame for this- immigrants couldn't learn English quickly so they simplified it.

At least in the US or the UK we don't have to explain to foreigners why we think windows are feminine.....

 

If you look up a word  using Webster's Dictionary it gives US and UK spelling, and usage also the use of the word in a sentence. In addition Webster's Dictionary  explores the origin of the word and when it entered the English language,. Also free online. IMO a superior online dictionary to the OED. Perhaps a discussion for the Nothing to Do About Coins strand.

Edited March 14 by ozjohn
More info

[david.bordeaux 166]

The Royal Mint Museum has confirmed that 28.30 mm is incorrect and according to "the data used in the Museum, sourced from the production records held in our archive" the diameter for all florins from 1893-1970 should be 28.50 mm.