Technical Research

The materials of the painting have been examined by eight independent Laboratories and their findings are summarized below.

The Canvas Support: The support is made of flax with a faint red earth colouring and is a tight, plain, tabby weave of very good quality. Although thin and tightly woven, the threads are uneven, indicating that the flax has been hand-spun and hand-woven.

'The Paint: Examination of paint samples by stereo microscope and comparison against reference slides identified the pigments red madder lake, yellow ochre, burnt sienna, lead white and Prussian Blue. All of these pigments (except Prussian Blue) have been used by artists from early times. Examination by scanning electron microscope revealed that the paint layer is particularly thin and in cross-section can be seen several distinct and discrete strata of paint, usually three, having the character of thin glazes. It also revealed that there was no evidence of pigment particles in the blue paint layer. 'The blue paint from seven diverse areas was therefore submitted to elemental analysis by energy dispersive x-ray, using an electron microprobe. This test established that it contained no iron or other metal elements, apart from a few inclusions of lead derived from the lead white ground, thus refuting the identification of Prussian Blue, of which iron is the main element.