Iconclass Iconographical Vocabulary

Iconclass (http://www.iconclass.nl) contains 28000 items used to describe the subjects of an image (persons, event, abstract ideas). Complete versions are available for English, German, French, Italian, and partial translations for Finnish and Norvegian

The main building blocks of Iconclass are subjects, used to describe the subjects of images. An Iconclass subject consists of a notation (an alphanumeric identifier used for annotation) and a textual correlate (e.g. 25F9 mis-shapen animals; monsters). Subjects are organized in hierarchical trees.

2 Nature
  25 earth, world as celestial body
    25F animals
      25F(+) KEY
      25F1 groups of animals
      25F1 mammals
      ….
      25F9 mis-shapen animals; monsters
      25FF fabulous animals (sometimes wrongly called 'grotesques'); 'Mostri' (Ripa)

Subjects can have associative cross-reference links between them (systematic references) and are linked to keywords that are used to search for them in Iconclass tools. Keywords form a network of their own, featuring see links (from one non-preferred keyword, not attached to any subject, to a preferred one), see also links (between keywords that are semantically or iconographically related) and translation links (between keywords in different languages).

Iconclass additionally provides with mechanisms (auxiliaries) for subject specialisation at indexing time. These actually allow for collection-specific extension:

by specializing a conceptual "placeholder" into a named individual (bracketed text) : 11H(…) saints can be specialized into 11H(VALENTINE), which does not exist in the standard Iconclass,
or by combining an existing subject with special auxiliaries (keys, structural digits, queues of keys, double letters): 25F2 mammals can be combined with (+33) head of an animal, resulting in 25F(+33) which can be used to index an image of a mammal's head. Or 11H(VALENTINE)2 can be synthesized from 11H(VALENTINE) and 11H(...)2 early life of male saint to index an image which specifically denotes the early days of the St. Valentine.

Maintenance of vocabulary is done via manual edition of semi-structured source files. As a general rule, the standard version shall only be changed in a conservative way, not modifying the existing subjects.