vermilion

Ingredients

mercury, sulfur

Preparation Steps

Original Recipe Text

The text discusses two historical recipes for artificial vermilion dating back to the tenth and eleventh centuries (Razi and Biruni). The key concept involves mixing fairly equal proportions of mercury and sulfur in a sealed glass jar with a narrow neck and a small hole on top. This procedure involves grinding sulfur with mercury, introducing the ground and blackened product into the jar, and slightly heating it in a special kiln (p. 189). For the application to the wall, soaked calcined calcite—or slaked lime—was mixed and heated with the pigment in a big pan before use as a paint layer (p. 182).

Evidence

"The red pigments which were highly correlated to Hg and S (the paints with a negative value of PC1) are most certainly vermilion (HgS)."

Remarks

The presence of orpiment as an impurity in the vermilion at Nishapur suggests it was artificially manufactured rather than sourced from natural cinnabar deposits, such as those in the Takab geothermal field, which typically contain barite (absent in Nishapur samples) (p. 189). Pigment use during the 9th-11th centuries in Nishapur is described as being in a trial-and-error stage (p. 175).