Do Herbal A and Herbal B correspond to differences in imagery?

[Linda]

In such case, maybe there are regions where red ochre is in deficit? Mountain, island, forest, or maybe certain specific part of the world? Is that possible?

According to wiki, the yellow ochre could be roasted to partially turn it to red. Presence of other minerals could also change the colour. Wiki:

During the Renaissance, yellow and red ochre pigments were widely used in painting panels and frescoes. The colours vary greatly from region to region, depending upon whether the local clay was richer in yellowish limonite or reddish hematite. The red earth from You are not allowed to view links. Register or Login to view. near Naples was a salmon pink, while the pigment from You are not allowed to view links. Register or Login to view. contained manganese, making it a darker reddish brown called terra di siena, or You are not allowed to view links. Register or Login to view. earth.You are not allowed to view links. Register or Login to view.
The 15th-century painter You are not allowed to view links. Register or Login to view. described the uses of ochre pigments in his famous treatise on painting.
This pigment is found in the earth of mountains, where particular seams like sulphur are found. And there, where these seams are, sinopia, green earth and other types of pigment are found...And the abovementioned pigments running through this landscape looked as a scar on the face of a man or of a woman looks...I went in behind with my little knife, prospecting at the scar of this pigment; and in this way, I promise you, I never sampled a more lovely and perfect ochre pigment...And know that this ochre is a common pigment, particularly when working in fresco; that with other mixtures that, as i will explain to you, it is used for flesh colours, for drapery, for coloured mountains and buildings and hair and in general for many things.You are not allowed to view links. Register or Login to view.