There are many questions relating to bronze coins - specifically pennies - in this period. I've formed some speculative theories of my own, but they are not yet ready for publication so for now this article will deal with the known facts relating to the bronze issues of this period; the penny questions which have not yet been answered will be raised, and the reader is free to speculate on possible answers.
Going in chronological sequence then:
In 1920, bronze was unchanged from the preceding years, which meant that the ‘reverse ghosting’ problem was as bad as ever (a faint outline of the deep cut obverse portrait in blank areas of reverse fields - which on the bronze denominations means the region from behind Britannia’s head down to her knees).
The next attempt to deal with ghosting was restricted - as was often the case - to pennies. In 1921 approximately half the mintage carried a lower profile ‘shallow cut’ portrait which as we have seen was introduced in 1920 for large silver. Almost identical to the previous obverse (see Freeman for full details), it was nevertheless flatter, and did partly reduce ghosting. This recut obverse, paired with the existing unchanged reverse, was used solely on pennies dated 1921, 1922 and 1926 (none were struck 1923-25), though there is a - probably - unique example dated 1920 in the British Museum.
Some specimens of 1920 and 1921 pennies are found with what looks like gold flecks on one side. There is no official explanation for this, but one suggestion is that unused WW1 brass shell casings were added to the mix, and that they failed properly to integrate into the alloy, leaving distinctive flecks. On the same tack - there was a slight change to the bronze alloy from 1923 (a reduction in tin) to soften the metal and allow greater ‘flow’, another minor attempt to reduce ghosting.
The first major variety (and mystery) concerns a discovery, back in the late 1970s, of a 1922 penny with a reverse that was distinctively different, but only to experienced eyes (same Britannia design, but not the same...). It has been described as ‘1922 penny-with-1927-reverse’, but this is not really the case. It does have many similarities to the 1927 reverse, but is also clearly distinct from it, as those who have seen it will readily admit. Some say the pointer to differentiate it from the normal 1922 reverse, is Britannia’s thumb in relation to St George’s cross on the shield. That is quite trivial : this extremely rare variety has a noticeably wide rim, and quite long teeth, as well as the whole design sitting flatter on the flan than the regular reverse. It has a rim wider even than that on the 1927 reverse, for example. It just looks different from both reverses, but very different indeed - to the experienced eye - from the ‘old’ reverse used for 1922 pennies.
Rare misnamed ‘1922 penny with 1927 reverse
However, the existence of this major rarity raises more questions than it answers. It was clearly a success story in almost eliminating the ghosting problem, so why was it not adopted on the next issue of pennies, in 1926? Yet it was not. Then there is the question of when exactly was this rarity struck: 1922, or later?
Moving on. Halfpennies. The similarly-sized shilling used the new ‘shallow portrait’ between 1920 and 1926, but inexplicably, this was not used for the halfpenny. Therefore the ghosting problem continued, as bad as ever. Struck with that deep obverse portrait and virtually no protective rim, the halfpenny reverse was subject to more wear than on any other denomination between 1911 and 1925. And so the Mint were compelled to make a more radical change to the obverse than had been seen up to then, and the Modified Effigy (M.E.) portrait was born (see the previous article - silver - for fuller details of the M.E. portrait). It was adopted in 1925 for the halfpenny, and not before time.
In late 1925 it was the first denomination to use the new portrait, which was paired with a modified reverse also - good rims, longer border teeth, and a slightly smaller and ‘flatter’ Britannia. This new 1925 halfpenny design is slightly scarcer than the number for this date with the earlier design, but it is still reasonably common. It was then used on all halfpennies dated 1926 and 1927.
The farthing’s tale is similar to the halfpenny’s, except that the M.E. portrait appeared first in 1926, for the entire issue, along with a similar modified reverse; the one main difference for farthings is that this new design carried through to the end of the reign, whereas both halfpenny and penny saw one further modification in 1928. But we’re jumping the gun...
In 1926 pennies reappeared, a low mintage of 4 million. Most of these used the same ‘shallow cut’ portrait first introduced in 1921 along with the same reverse used since 1913. However, a small proportion of this run bears the M.E. portrait - possibly numbering tens of thousands, the precise mintage is not known. This, the famous 1926ME penny, has always been very scarce, but incredibly rare in the top grades. It probably vies for rarity with the 1919KN. The reverse on the 1926ME pennies was not modified with the new portrait, unlike halfpennies and farthings, and therefore the 1926ME has sometimes been described as a ‘mule’ (obverse and reverse not matched).
In 1927, the M.E. portrait was again used for the obverse, but this time the reverse was amended : Britannia is slightly smaller and more compact, the rim is a bit bigger, the border teeth are longer, the lettering smaller, and the exergue larger. The net result of this change, is that the reverse is flatter (especially combined with the M.E. portrait) rather than having the ‘dished’ look that was evident especially before 1921. The modified reverse is similar - with the exception of the denomination - to that introduced for the M.E. halfpennies in 1925, and all farthings from 1926 (see above).
The Modified Effigy draws a final line beneath the ghosting problem, though that was finally obliterated by the changes brought in from 1927/28, and which will be described in the next and final article. For the Royal Mint it was a long and bumpy road which persisted through the several attempts to cure it, and they must surely have breathed a sigh of relief when ghosting became merely the ultra-faint phenomenon to be seen on some coins of so many reigns, and not the ugly disfigurement it was between 1911 and 1926.
There is a postscript, raising the biggest mysteries and unanswered questions of all. In recent times, two so far unique pennies have been discovered, one dated 1922, the other 1926. These are both startling in their own way, and I have left them to the end as they cannot be slotted conveniently into the existing chronology, however much commentators and researchers may wish to. I hope my own speculations on the subject will be published before too long.
The 1922 penny has the very rare experimental reverse discussed above, the so-called ‘1922-with-1927-reverse’. However, and almost unthinkably, it has the Modified Effigy obverse! To account for this coin will require some very radical thinking indeed.
The 1926 penny is a bit less startling, but nevertheless still a surprise. It has the Modified Effigy obverse, but the reverse is the actual change of 1927, though dated 1926. It has a sharp appearance, almost prooflike according to Michael Freeman, and is obviously a special striking. I've had to bring some radical thinking to bear on the problems raised by these two pennies, and I hope to have them ready for this website by Christmas.