This is a very hard to solve issue.
Out of the real/not real ref #s, the problem is that not all catalogues assign numbers with same rulers (and of course we all have seen Krause using different rules on the same variation).
I think current 5 ref #s are enough, if they can include all the variations.
Will explain to be clear:
We don't follow any catalogue classification for split or merge pages. That's great!
Mostly, we merge coins/notes that evidence to be from the same general design, variations may be different years, different dies (specially aged ones, for dies were hand-made, so variations are expected).
We know the most used catalog by everyone is Krause. We all know they have different rules to assign ref #s, and while they give same generic # in a case, they give different in others, with the same variation.
Now, I think is usual for collectors who “specialize” on certain countries, regions, eras, etc., they prefer to use the local catalogs, or the theme catalogs, since they have better information, and ussually more accurate than the world catalogues (Kruase, Yeoman, Schon, etc.).
I have seen in many cases, they tend to split more the #s, and on the Spanish speaking countries (may be in others too), they use to give the generic # based firstly on years (Argentina-Bottero, Janson; Cuba-Aledón; Brazil-Amato, Bentes; Colombia-Restrepo; Spain-Calicó; Uruguay-Silvera, Rotondaro, CG; etc.).
A few examples:
Argentina 1 Centavo 1882-1896:
Krause: KM# 32, Janson: CJ# 38 to CJ#51, including 1885 variants CJ# 41.1, 41.2 and 41.3.
All are listed on the same Numista page., On Krause 1 Ref #; on Janson 13 Diiferent “Generic” Ref#s, or 15, with variants.
Cuba
(example given by Ole at start of thread) 5 centavos 1981-1989:
Krause KM# 412.1, 412.2 and 412.3; Aledón JMA# MC4, MC5 (they consider KM# 412.1 and 412.2 the same, or didn't noticed the variation); Schön 706.2;
5 Centavos 1989:
Krause KM# 412.3a; not listed on Aledón, variation is different metal, steel instead of copper-nickel, and thin typography.
Diferent case:
10 Centavos Intur 1981:
Krause KM# 415.1; Aledón JMA# MC9;
10 Centavos Intur 1981-1989:
Krause KM# 415.2 (both years); Aledón JMA# MC10, only 1989, the other does not exist;
10 Centavos Intur 1989:
Krause KM# 415.2a; Aledón JMA# MC8;
10 Centavos Intur 1989:
Krause KM# 415.3; Aledón not listed.
Each one is a different Numista page.
First Cuban example has the problem that so far there are 6 different ref#s, and may be more (I have other local catalog, by Roberto Menchaca García. In this catalog doesn't assign ref #, but used Krause notation, they list 1 more variant, corresponding to KM# 412.3a. Taking into account the missing listings, would be a total of 9 or 10 variants (not sure if the separate con is the same for Schön, or it has a different ref.; also as shown ref is 706.2, I assume the variants may have different numbers or sub numbers; I don't have Schön, so I don't know their way of notation.
The second Cuban case is an alternative to have separated pages for each type of coin (simmilar to Krause style, they list separately sub types). This example has the problem that when a collector only is interested on coin types (not interested on variants), they would have several pages for each type instead of only one. If they register 415.1, then 415.2 and 415.3 will show as not having the coin. This also means collector needs to be aware of the variants, and check each page before knowing if they have or not their target made. In other words, when selecting “hide coins I have” will show as missing types they really have.
My idea is to have 5 refferences, one for a different catalog, with the possibility of registering different numbers for each in same line, maybe separated with commas, slashes, or whatever may be used, and the searh be made towards included ref. (would look for something between a space and a comma; Xavier would find the correct way for the search).
In the case of Argentina example, they could have:
KM# 32 (searching for KM# 32 will find it)
CJ# 38, 39, 40, 41.1, 41.2, 41.3, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51 (searching by 38, or 40, or 41, or 4.2, will find it)
In the case of Cuban 5 cents, refs list would show as:
KM# 415, 415.1, 415.2, 415.3, 415.3a (generic “415” may be avoided or included, depending of the programming parameters)
JMA# MC4, MC5
Schön# 706.2 (etc.)
Hope this idea may help to decide how to solve this problem. Any additions to improve it will be welcome, for sure.
Just 10 options: you understand binary, or you don't.
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