A catalogue raisonné is an exhaustive descriptive catalogue of all of the works by an artist, artistic school, or movement, which are known at the time of the catalogue’s compilation. The inclusion of an artwork in a catalogue raisonné is often considered to be the definitive signifier of authenticity, and accordingly extensive research and care is demanded in their compilation.
A diptych is a two-paneled artwork, which is sometimes hinged, or shown side by side. It was first used in Roman folding tablets, as a way to send messages. The form then was adopted for altarpieces in Christian churches. It has come to be used for secular subjects, including companion portraits.
The term ‘gestural’ is used to describe a style of painting in which the artist’s gestures as they apply their chosen medium are emphasized, to draw attention to the physical process of making the artwork. The term is often associated with the Abstract Expressionist and Expressionist art movements.
Medium describes both the type of work done by an artist; ie sculpture, painting, drawing; and the exact elements that compose the artwork, such as an oil painting on canvas, or a charcoal drawing on paper. It is also the term used to describe the liquid in which dry pigment is mixed, in order to make paint.
Oil paint is formed from the mixture of pigment with an organic oil, known as the medium. The resulting paint is slow drying, and mixes well to create a wide range of colours and textural effects. Oil paint may also be diluted with paint thinners such as turpentine, to make the application easier, or change the visual effect.
Sfumato is the term used to describe a misty quality that softens the contours in an artwork. Sfumato blurs the contrast between light and dark, and can create a ‘soft focus’ effect. The term derives from the Latin word for smoke, and is often used in relation to Leonardo da Vinci, who is credited for developing the technique.
Surrealism was a movement in literature and art, which was popular between the First and Second World Wars. Founded by the poet André Breton, the movement emphasized the importance of unconscious thought as a starting-point for creativity, inspired by the work of Sigmund Freud. Surrealist artworks are signified by their juxtaposition of incongruous imagery and figurative, typically photo-realistic style.
A triptych is a three-paneled artwork. The panels are sometimes hinged, and the outer panels may fold over the central panel. Triptychs were historically used primarily for religious purposes, as altarpieces, or to encourage private devotion. In modern usage artists have appropriated the form for other subjects.
X-radiography, or X-ray is used in technical examinations of paintings in order to better understand the methods employed by artists. As a non-invasive imaging method, X-rays can reveal compositional changes, underdrawings, areas of retouching and earlier paintings present in the underlying surfaces of the finished artwork.