For statistics purposes, an artwork is automatically classified into a media category based on the first word or words in the artwork's media description.  We use the first words in the description because the usual convention in describing the medium of an artwork is to list the most abundant material first.  For example, an artwork that is mostly watercolour with some gouache highlights should be described as  'Watercolour and gouache', and would therefore be classified under 'Watercolour' for the purpose of our statistics. Please note however that the auction houses may not follow this convention for every artwork.  We will continue to monitor the way the auction houses describe the medium, and make changes to our classification rules if necessary. The classifications, and rules for assigning artworks into those classifications are outlined below:

Oil - This includes all artworks that are created mainly with an 'opaque pigment'.  Therefore, artworks that have a medium beginning with the words Oil, Acrylic, Synthetic polymer paint, House paint, Enamel, Ripolin, Tempera, Egg Tempera, Gouache, Natural Earth Pigments, Earth Pigment, Natural pigment, Spray, or Ochre are assigned to this classification.

Watercolour - A separate classification has been created for Watercolour artworks as it is quite a separate discipline from 'oil' painting, and there can be a significant difference between the price of oils compared to watercolours for most artists, with watercolours being generally cheaper.  There are exceptions to this rule where an artist is reknowned for their skills in watercolour, and therefore may command higher prices for watercolours than oils.  Norman Lindsay , Paul Jones and J.J. Hilder are possible exceptions.

Artworks that have a medium beginning with 'Watercolour' are included in this classification.

Drawing - This classification is for artworks that have a medium description beging with Drawing, Ink, Pencil, Pen, Charcoal, Ballpoint, Coloured pen, Conte, Crayon or Chalk.

Pastel -  Although pastel  artworks could easily be classifed  in the Drawing classification, pastel can also be considered to be a separate discipline, with some artists such as Janet Cumbrae-Stewart specialising in the medium.  Artworks that have a medium description beginning with 'Pastel' or 'Dry Pastel' are included here.

Mixed Media - For atworks that use a combination of media, with no one dominant medium.  Artworks that have a medium description beginning with 'Mixed Media' are included here.

We welcome comments and suggestions on our classification rules.