General material designation

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The general material designation, or "GMD," is a term or phrase inserted in brackets following an item's title in a catalog record to allow a user to quickly determine what type of material the item is - for instance, "manuscript." The GMD was encouraged by the cataloging standard AACR2, which assumed that the majority of a collection would be books, and that any other types of materials (such as manuscripts, microfilm, or audiovisual resources) should be specified. The GMD is slowly being phased out of library catalogs, as new standards and interfaces allow for other ways to display its information. However, the Folger has chosen to continue using and displaying select GMDs in Hamnet at this time.

Cataloging policy

  • GMDs should always be added to manuscripts, electronic resources, audiovisual resources, realia, and microforms, among others; refer to the full list below.
  • The GMD is always lowercase and contained inside a set of square brackets.
  • The GMD is added to the MARC 245 field in a subfield ‡h. It follows the subfield ‡a directly, and precedes all other subfields and information, including punctuation.
245 00 ‡a Book of magic, with instructions for invoking spirits, etc. ‡h [manuscript], ‡f ca. 1577-1583.
245 00 ‡a Jonson 1623 ‡h [electronic resource] : ‡b a new almanack and prognostication for this yeere of our Lord God, 1623 : being the third from the leape-yeare : calculated according to art, for the meridian of the famous city of London, ... and may serue for all England / ‡c by Iohn Ionson ...
  • Exception: if cataloging manuscripts to the DCRM-MSS standard, add a descriptive GMD at the end of all other title information but before the statement of responsibility. See DCRM-MSS section 1D for additional information.
    • Most manuscript catalog records at the Folger use [manuscript] as a GMD, but occasionally have more descriptive GMDs that can look like free text; check with your supervisor or the curator of manuscripts before altering or removing this information from a record!

Searching GMDs in Hamnet

On the Advanced Search tab, select "Material type [GMD]" from the drop-down menus next to any of the three search boxes, and enter a term from the list below. You can search by GMD alone, or combine it with other searches.

List of GMDs in use at the Folger

Catalogers should consistently apply the following GMDs to relevant materials:

cartographic material
electronic resource
game
graphic
kit
manuscript
microform
motion picture
music
realia
sound recording
videorecording
  • NB: per DCRM(G) and gihc, the GMD "graphic" and the fixed-field code "k" are used for all two-dimensional still graphic materials (including projectable graphic materials).

Other GMDs may appear in preliminary Hamnet records, and legacy Hamnet records.