Hello.
Again I will reason about Pick: There is not a clear rule for split or merge types; sometimes they make new types just for be different issuing years, in other cases they are merged in a single reference number and in other they are merged, but with a different suffix (##a, ##b, etc.). Same thing about printers, some are merged, some are split; and even they split owing to very subtle differences, or merge even if the differences are noticeable.
My mind is about make a page for each different GENERAL DESIGN it is very usual subtle changes are added on the different issues, but at first glance notes look the same, you need to search for the details to realize they may be different.
On the other hand, collectors may use different criteria for their collections, some look for types only, so if text have a small change, there are different number of signatures, serial# has 1 more digit, different series, different years, and the signatures combination…. We must detail them, but we should have a clear rule of what to merge or split. When a collector looks for “all variants” will be the same if they are split or merged; for those looking for “types”, merging them would ease things; and when someone looks for a particular criteria, having they merged would ease things too; they would have all the variants in same page, and is easier to determine what they need to find.
As collector, I use different criteria on different ranges of collection:
I only collect coins and notes from Latin América and Caribs, but with different “rules” for regions or countries:
Uruguay: All types and series, but I don't care about combination of signatures.
Cuba: All notes, whichever be the variant, series, years, signatures, types, etc.
South America: types and printers, but don't care about signatures, series or years.
Rest of América and Caribs: types, I don't care about signatures, series or years: if I may get different printers is OK, but nor critical for me.
And for South América (coins): 21st Century (2001 to date); every coin and variants, including years, minthouses, etc.
I think creators of catalogs have a great problem determining how to assign codes and sub codes (variants).
As example:
In my country, Rotondaro catalog have 2 versions; one for notes issued by Banco de la República Oriental del Uruguay (1896 to 1967) and the other for notes issued by Banco Central del Uruguay (1967 to date).
In the first one he used a code of 3 parts: using a combination of Arab and Roman numbers in the form of AAA.RRR.AAA. First number (AAA) was for the group of notes printer under a Law. (Law of 1935=9; Law of 1939=10); second number (RRR) was the face value of the note, and the last (AAA) was the variant, maybe different series or signatures combinations, and also overprints, etc., but with the particularity they were added in sequence for series and serial #s, even if the series and signatures repeated other previous.
ROT# 9.II.1: Law of 1935, 50 Cents, series A, signed by Bank President and Government delegate, # 00 000 001 to 02 197 964;
ROT# 9.II.2: Same as previous but signed by Bank Vicepresident, # 02.219.765 to 02 696.794;
ROT# 9.II.3: Same as previous, but again signs Bank President, but is other person #02 758 094 to 02 298 719;
ROT# 9.II.4: Exactly the same as variant 2, # 02 906 181 (only known); this variant is caused by serial is not following the 2nd.
Total 10 different variants.
ROT# 9.III.1 to 9.III.15: Law of 1935, 1 Peso, series A, 15 variants; again some repeated.
ROT# 10.III.1 to 10.III.27: Law of 1939, 1 Peso Series A, B, C, D, 27 variants.
Now, on the second catalog, about Central Bank, changed the rules:
In this case he used number, letter and number
First number was consecutive for the order of appearance, but the same for same face value and general design. Letters were for the series, adding “R” for reposition issues; and the last numbers were the variants, if they existed; if no variantes may not be added. In this case, variants were assigned due to different years or signature combinations.
In resume: I would like to merge notes when they have the same general design, unless important changes, like currency reform or different size and/or material (paper/hybrid/polymer). This way, users will be able to know there are variations on a note, if they mind, and will have them all in same place.
Last: Other reason to have them merged is, if a user search for an issuer=>face value=>year, if they are split will not know if there are similar notes with other years.
Regards,
Daniel,
Uruguay.
Just 10 options: you understand binary, or you don't.
Catalog Referee Coins, Banknotes & Exonumia: Uruguay, Cuba, Bolivia, Brazil, Chile, Colombia, Mexico, Peru, Paraguay, Costa Rica, Venezuela, Panama, Ecuador, Zamunda, Parva Domus and more.