Given that, in Numista, circulation types actually issued for circulation are always listed along with non-circulating issues provided they are of the same type and specifications (diameter, metal, etc., but different finishes OK), then IMO there is no reason to create a new page.
Also, according to this principle, New Zealand circulation types would need to be entirely reorganized since many years of circulating types are only released for collectors. For example the standard kiwi dollar in 1999–2020, with those years with only collectors issues underlined. The years in bold were issued for circulation but also (of course) for collectors:
1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2013 2015 2019 2020
None were issued in the missing years. I don't think any was issued after 2020.
Now imagine, for the sake of argument, that the dollar under Charles III is issued for circulation in 2025. Then it's not issued in 2026, nor in 2027… What do we do? Do we wait a number of years and reassign them to a new page and number? Oh! But then, the 2028 year is issued for circulation… Do we move 2026 and 2027 back?? This doesn't make much sense.
If anything could be changed, it's that “proof-like” (i.e. NBU) be given their own page, likewise proofs and specimens. I made myself a checklist for US cents from the Fugio to now which includes only circulation coins, so, for example, none of the “S” cents in the past several decades belongs to the list.
In the case of the Canadian 50 cents, no change happened to the coin since 2003 when the 4th portraitr was introduced. It's also at that time that the Mint stopped selling them at face value for circulation.
However, I think I know what happened… The 2016 Annual Report still listed the 50c along with circulating coins (p. 86), while it was removed from the same table in 2017 (also p. 86) and 2018 (p. 97). In 2003– 2016, I think the only reason to list it there was because it was a circulation strike, though sold only to collectors. I suspect the expert who contributed to the Krause relied on the RCM reports and noticed the change, i.e. that the 50c was removed from the stats for circulation coins, but IMO it's not reflective of any change in the legal status of the 50 cents. My view is confirmed by the fact that the 50c is still listed among circulation coins in the authorization for the new Charles III circulation coinage. It's a legal technicality, and I have found no legislation in 2016–2017 that changed the status of the 50c.
So, the 50c in 2025 remains technically a circulation denomination, but it is never issued as such; it's always issued above face value in rolls and sets to coin collectors. One day the Mint may ask the government to pass legislation to remove the 50c from the list of circulating coins, which would mean a revision of the schedule appended to the RCM Act. However, those people know that in the case the “nickel” is discontinued, the 25c will have to go as well, and a 10c / 20c / 50c / $1 / $2 system would make sense.
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