Proof sets of the first issue of Rhodesia and Nyasaland coins were issued in 1956 - the Central African Currency Board had asked in 1955 if the coins could be struck in silver rather than curponickel as the circulating coins were cupronickel, and the Royal Mint was able to oblige and strike the proof sets in .500 silver (p57, Hodgson, The Rhodesia and Nyasaland proof set of 1955 in Coin News, March 2023).
Although all 2,000 sets were struck in .500 silver, a number of catalogues list 1955 cupronickel proof sets as having been struck as well, though this is not the case. The origin of this error is unknown, but individual cupronickel proofs were struck for institutional collections (p58, Hodgson, The Rhodesia and Nyasaland proof set of 1955 in Coin News, March 2023)
As with many previous years, in 2005 the Royal Australian Mint struck a non-circulating one dollar coin that was available to counterstamp and purchase at locations throughout Australia. In 2005 the one dollar coin was commemorating 90 years since the beginning of the Gallipoli campaign in 1915, and besides being available to counterstamp in Brisbane, Sydney and Melbourne (with B, S and M counterstamps respectively), it was also available for counterstamping at the Australian War Memorial in Canberra with a G counterstamp.
Around 40,000 coins were counterstamped at each location, however a small number escaped with no counterstamp. McDonald said 2 examples were known in 2013 and that one appeared to have been released at the Australian War Memorial (p160, McDonald, 2014 Pocket Guide to Australian Coins and Banknotes, 2013). In March 2023 Drake Sterling offered an example for sale with the note that fewer than 10 were known, though it did not state at which location the example was released (Eigner, https://www.drakesterling.com/australia-2005-gallipoli-one-dollar-missing-counterstamp-pcgs-ms66-45315100).
Davies reports two varieties of the 1887 Gothic florin - one with 33 trefoils/arcs in the obverse rim (Davies 779) and one with 46 trefoils/arcs in the obverse rim (Davies 780), though Davies 779 is listed as unconfirmed.
While its existence is unlikely given that the date is on the obverse, it is not impossible for Davies 779 to exist. Dickinson however never saw an example (p146, Dickinson, Victoria "Godless" and "Gothic" florins - A further report in Seaby's Coin and Medal Bulletin, May 1980), and while not outright dismissive of its existence, was certainly doubtful. Since then no example has been publicised so it is probably correct to assume that Davies 779 does not exist.
Why the coin was originally thought to exist is probably lost to time, but a worn example being misattributed seems unlikely, as 33 is quite different to 46, even on a small coin.
In 1970 the Royal Australian Mint issued its first commemorative coin - the Captain Cook 50c piece. Curiously, it was also the first Australian decimal coin to exhibit date varieties.
On some 1970 50c pieces the 7 in the date is parallel with the rim while on others the 7 in the date is not parallel with the rim. Neither variety is rare although the 7 not parallel with rim is more common, accounting for around 65% of circulating coins, while the 7 parallel with rim is less common, account for around 35% of circulating coins.
It is unclear if both date varieties occur in mint or proof sets or in the specimen 1970 Captain Cook 50c pieces.
In 1994 the Royal Australian Mint issued a commemorative 50c piece for the Year of the Family. The coin is quite common but is one of a few Australian decimal coins that has date varieties.
On most 1994 Year of the Family 50c pieces the date is narrow and the digits are approximately equally spaced. On a small number the date is more widely spaced: the 1 and 9 are similar to the narrow date but the 9, 9 and 4 are further apart than the 1 and 9. While the wide date is uncommon it is not excessively rare: the narrow date accounts for around 94% of 1994 50c pieces in circulation while the wide date accounts for around 6% of 1994 50c pieces in circulation.
It is unclear if both varieties occur in mint, baby and proof sets and if they do, in what proportions.