As this was a period when some of the finest examples of illumination were produced, it is interesting to note the various colours used, so they are given in detail.
The reds mentioned by him are sinopia, cinabrese, cinnabar, minium, amatisto, dragon’s blood, and lake. Sinopia is a similar colour to light red, either native or prepared by roasting yellow ochre. Cinabrese is a mixture of sinopia with chalk. Cinnabar, as mentioned before, is mercuric sulphide, which, when artificially prepared, is termed vermilion. There is hardly any doubt that the variety Cennino was familiar with was the artificial kind, for he remarks that it “is produced by alchemy, performed in an alembic.” Minium is red lead, while amatisto is probably hæmatite. Dragon’s blood, as already referred to, is a resinous colour, and lakes were prepared from various dyes.
The yellow pigments were ochre, giallorino, orpiment, risalgallo, zafferano, and arzica. Giallorino is supposed to have been a native mineral yellow pigment. It is described by Cennino as a volcanic product. Some, however, think this to be similar to the pigment that used to be known as Naples yellow, which was a compound of the oxides of lead and antimony. Risalgallo realgar, or red orpiment, was prepared by gently heating orpiment. Zafferano was saffron, while arzica was a lake prepared from weld, which is wild mignonette.
The greens that he refers to are verde terra, verde azzurro, and verderame. Verde terra is the natural earth known also as terra verte. In all probability verde azzurro was a native copper carbonate, similar to green bice. Verderame was verdigris.
The blues used were azzurro della magna, azzurro oltre marino, and indaco baccadeo. Azzurro della magna was a copper-blue similar to the azurite of the classical period. Azzurro oltre marino was the genuine ultramarine. Cennino’s description of the preparation of this pigment from the lapis lazuli is very similar to the recipes that are given in other MSS. Indaco baccadeo was indigo from Bagdad.
The white pigments were bianco sangiovanni and biacca. Bianco sangiovanni was whiting or chalk, while biacca was white lead.
The blacks were “a soft black stone,” black “made of the young shoots of the vine, which are to be burnt, and when burnt, thrown into water, and quenched, and then ground like other black pigments.” Another black pigment “is made of the shells of almonds, or of peach-stones.” Lampblack was also used.
The colours were mixed with gum arabic or egg.
Cennino also makes mention of the use of the pezzuole colours, or clothlet tints, which were used a great deal in the Middle Ages. These were pieces of linen stained with transparent pigments. When required for use, a small piece was cut off and soaked in water to make a tint of the colour, a little gum being added.
Cennino also treats of tinting parchment with various colours. This was not done, as was the custom in the earlier period, by staining the vellum with a dye, but by washing a colour over it with a large brush.