Recent diagnostic investigations on Leonardo da Vinci’s the Adoration of the Magi, conducted by Maurizio Seracini, have revealed that the painting was carried out in two distinct stages, during two different time periods (a).
During the first stage Leonardo applied, on a panel made of an assembly of ten poplar planks (b), a ground consisting of layers of coarse and fine gesso bound with animal glue (c). He then developed a detailed brush drawing with lamp black and natural resin. This was covered with a thin priming of lead white, transparent enough that the drawing would remain visible during the painting phase (d). The only area that Leonardo went on to paint substantially was the sky, which is made of a mixture of lead white and a little ultramarine. He also applied occasional highlights to some of the figures and parts of the architecture (e).
A second stage came much later, when another artist added several layers of paint made of red and brown earth pigments, copper resinate and a lot of charcoal in oil with some resin (f). These monochrome layers do not follow the lines of the underdrawing, instead largely obscure it.
In summary, Leonardo’s magnificent creative moment in the Adoration is represented by the superb preparatory drawing, which can once again be admired thanks to the results of scientific studies (g, h, i).
In the preparatory drawing on paper, Leonardo first traced the architecture and a large covered structure on top of meticulously-drawn lines of perspective (j). He then went on to fill in the scene with figures and horses, sketching first in charcoal and then adding greater detail with iron gall ink (k).