Collections Link - Just Practical Advice - 0845 838 4000

Re-numbering

This document was written, and licensed for publication by the Collections Trust.

Collections are often faced with documentation numbering systems that seem muddled and confused. Some think that a solution to this is to start from scratch and give every item in the collection a new number. This is usually a bad idea and when the Collections Trust is approached by museums considering re-numbering we always advise strongly against it.

Why not?

1. Numbering systems don't have to be neat to be effective
An accession number should link the object to the information about it. If you are able to pick up an object in your store, look at the accession number and then locate all the information relating to it then you don't have a problem with your numbering system.

For example, it doesn't matter if from 1920 to 1950 numbers could have been written as '13267; 13268; 13269; 13270'. Then from 1950 they changed to '1950.1; 1950.2; 1950.3'. Then three different departments started their own numbering systems or using different types of number for different types of object. The accession number is only a code for linking the object to the information about it - as long as the code is unique to every object and links the object to its documentation then formats do not matter.

A Collections Trust Adviser says:

'Our system has changed three times over the last 35 years. The first two systems were fine while the collections were small, but needed improving as the collection grew. It has not been necessary to go back and re-number objects, as every object had a unique number. The changes in the numbering systems show how the museum has grown and adapted to change.'

You may need or want to change your numbering system, for example if you have been using running numbers and these have got too long. However, you can do this from now on and do not need to go back and change existing numbering systems.

2. Old documentation is important
Old accession registers are rarely 'tidy' or 'correct', and may well not be organised as we want them today. However, they were written as they were for a reason and are very important records - often the most original source of information you may have about your collection. Old accession numbers can be significant and often give us information about how the collector perceived the collection, or how the collection was organised. An accession register and its accompanying numbering system is a historical document. It can never be 'perfect' but it tells its own story.

3. It is a huge task to undertake
Re-numbering collections doesn't just involve allocating a new number to every object in a database or catalogue. You will also have to make decisions about how you are going to link your old and new numbers. For example, are you going to mark each object with its new number? How are you going to cross-reference all your existing documentation to the new number? This is a lot of work to undertake unnecessarily and your resources could be better used.

4. You may just be creating another problem for the future.
Museums often think about re-numbering their collections because several, seemingly confusing systems, have been used in the past. Will you just be adding to this confusion? If you don't manage to re-number your entire collection and cross-reference every piece of documentation to the new number you will be creating yet another half-finished system.

This is the experience of one Collections Trust Adviser:

'A previous curator re-numbered a small part of my museum's collection and it is still the bane of my life. They didn't re-number all the pieces, probably because many were physically too small for more than one number. The accession register and the collection catalogue still use the original numbering system - so I can't work out if we have items missing or duplicated.'

5. Computers can cope
Accession numbers don't need to be 'intelligent'. They don't need to contain catalogue information such as a classification code or storage location. An accession number is a unique reference number, whose only purpose is to help you find the right entry in your recording system. Additional information, such as storage location, should be stored in additional fields of information in your cataloguing system. Computer databases allow you to find this information easily and quickly.

Some better ideas

Below are some fairly common problems with numbering and the solutions that we recommend in preference to re-numbering:

  • How do I deal with gaps in the numbering system? For example, the number sequences in the registers jump from 1953.1 to 1953.3.

This often happens if accession registers have been reconstructed retrospectively. For example, if objects were allocated numbers and marked with them but the information was not recorded in an accession register. If you are still able to link the objects to the information then your numbering system does not need changing. The accession register is also an important document even if you know that it was created some years after the objects were acquired.

If there is a gap in the accession register you can annotate this with your initials and the date to explain what has happened. You could also create a catalogue record explaining why the number is 'missing'. If you found what you suspected was 1953.2 then best practice is to give it a new accession number and enter it into your current accession register. You should record that it was found in the store and is probably 1953.2.

  • In the past long-term loan items were given accession numbers. These loans have now been returned to their owners but there are still records for them in the accession register.

Under today's standards loans should not be accessioned into the permanent collection. However, if previously accessioned loans have been returned to their owners you do not need to re-number collections so that you do not have 'redundant' numbers in your Accession Register. Redundant numbers do not matter and can provide valuable information about the history of an object while it was in your care. Just note in the Register that the object was taken in as a loan and has been returned, sign it and date it. You should back this up with a receipt from the owner saying they have had their object back.

  • Nothing has been accessioned since 1993. We can't start to deal with the backlog because we don't know always know in which year objects were acquired, so we can't give them the correct accession number.

Using an accession number format which contains the year (eg 1953.2) does not mean that backlog objects have to be accessioned with a number for the year in which they were acquired. The date an object was acquired should be entered in a separate field in the database or cataloguing system. For example, if you were carrying out backlog accessioning in 2004 for objects acquired in 1999 these objects should be given 2004 accession numbers and the acquisition date recorded separately as 1999.

  • We acquired a collection of objects from another organisation a few years ago. The objects in this collection are marked with up to three numbers each but none of the numbering sequences are complete.

In this situation creating yet another numbering system would probably be more confusing and marking the objects with another number could potentially spoil them. The best solution would be to choose one of the existing numbering systems to use in the accession register. This would depend on which is the most complete sequence, whether it was possible to work out which was the most original number and which had the best accompanying documentation. You would need to record why there were gaps in the numbering sequence and make sure that the other numbers were cross-referenced.

  • We know that our accession register has been re-written at least once in the past and that older versions were thrown away. The accession register we have now is not original and is unreliable.

This is not an argument for creating yet another version of the accession register. Firstly, if the numbering system works in linking the objects to information about them then it is not necessary to re-number. Secondly, you may know that your existing accession register is not the 'original' but it is the most original source of information that you have. Information may seem inaccurate but it was recorded for a reason and it is important to retain it. You can still annotate the accession register if necessary with you initials and the date or record queries in your catalogue record.

A final recommendation

Carry out a retrospective documentation project. In all the cases outlined above a better use of resources would be to carry out a retrospective documentation project using the existing documentation. The Collections Trust provides a range of resources to help you with retrospective documentation and a good starting point is the Retrospective Documentation and Making an Inventory factsheet. You can also get individual support from the Collections Link enquiry service.

Sources of help and advice

The Collections Trust provides impartial resources for all aspects of collections information management. For more information please contact: Collections Link - 0845 838 4000.

Version 1.2 - Last updated July 2008