Most authorities agree that they are frescoes-painted directly on wet plaster.

Until the 15th century, artists painted on plaster, stone or wood, where the frame was integral to the work.

The walls of these rooms were probably also painted on plaster, but no traces survive here.

"You're doing your work out in public, on wet plaster, and everyone sees the process."

Her gum tore open on the rough paint and plaster.

Done in tempera on plaster from 1937-39, each deals with a different Manhattan area.

Others are made from painstakingly detailed pencil patterns on plaster.

That year the pair travelled to France to study oil painting on plaster.

Painting on fresh plaster means that the artist can spread the paint much easier.

It might be close to impossible on dry wall, but is easier on plaster.