Are Michel Katalog numbers subject to revision, as Scott Catalogs are? As I am not concerned with Michel values, can I use an old edition for identification purposes and be sure that the catalog number is still the same?
In my experience Michel does not change the numbering. Sometimes the set up of countries is changed. For example the South African homelands - Ciskei and so on - in older editions were listed as separate countries but are now listed with South Africa.
Collecting the world 1840 to date - one stamp at a time! 09 Oct 2016 01:39:36pm
re: Are Michel #s subject to revision?
Agree with Gerben/SWH - Michel numbers are amazingly static. When/if they change catalog identifiers, then it usually part of some bigger change. That said, some countries to look out between old/new Michel #s are Russia (changed in early 2000s if I recall) and Egypt (changed in 2014).
The trouble with Scott is that they want to group sets of definitives or commemoratives that belong together. If the set turns out to be longer, they need to renumber a lot of stamps and if there are less than anticipated you end up with numbers that are not assigned. In any case it is rather chaotic and undesirable. Michel sticks to a strictly chronological numbering and adds references or overview tables at the end of the listing.
I am sure there are exceptions, but as far as I know, new stamps are first catalogued in the Michel Rundschau magazine and the number that is consigned there, will not change anymore. It used to be different in the past as some long series are combined from issues that were done over a number of years, but I think this is the case for the last fifty years or so.
Scott used to change numbers quite frequently. This was done, for example as follows:
1990 catalog:
Country D
Catalog number 321 ultramarine value $4.50
Catalog number 321a green value $5.25
In a few years, Scott determines that the value of the major number increases and becomes higher in value than the minor stamp.
1994 catalog:
Country D
Catalog number 321 green value $5.25
Catalog number 321a ultramarine value $5.50
They used to do this all the time. They finally listened to the collectors who were tired of having to swap out their stamps each year with the flip flopping of catalog numbers.
You see the result of Scott's cessation of flip flopping numbers in the classic era with the removal of major catalog numbers from the standard catalog and listing the lower valued minor numbered stamp in its place. The major numbered stamp, along with the minor numbers are only listed together in the classic specialized catalog. A ploy that serves two purposes: 1 - stops collectors from having to flip flop stamps in their albums; 2 - makes collectors have to purchase the more expensive classic catalog along with the standard catalog in order to get listings for all the major numbered stamps for a large number of countries.