Cinnabar is the natural mineral form of mercury sulfide, ground and purified to produce a brilliant and highly opaque red pigment. Described by Pliny and Vitruvius and found in Roman frescoes at Pompeii. Synthetic vermilion, chemically identical, was developed in China and transmitted to Europe via Arabic sources by the 8th century CE.
Extensively used as a red writing ink, with its primary purpose being the rubrication of manuscripts: marking titles, initials, and important passages.
The pigment can darken to black through conversion to metacinnabarite (a different crystal form of HgS) when exposed to light and moisture, particularly in fresco. Most stable when protected by oil or varnish layers. Extremely toxic during preparation. Gradually replaced by cadmium reds in the 20th century.
Usage Timeline:
| Pigment | Prehistory <3000 BCE | Antiquity 3000 BCE–500 CE | Medieval 500–1400 CE | Early Modern 1400–1800 CE | Industrial 1800–1950 CE | Present 1950–today |
|---|---|---|---|---|---|---|
| Cinnabar (Natural) | ||||||
| Vermilion (Synthetic) |
Key Properties:
| Properties: | Brilliant orange-red to scarlet; Opaque, High tinting strength; Dense, heavy particles |
| Usage: | Antiquity to early 20th century; Synthetic: 8th century CE to early 20th century |
| Source: | Artificial/Alchemical |
| Toxicity: | Highly toxic (mercury) |
| Fresco: | Limited (darkens) |
| Tempera: | Yes |
| Oil: | Yes |
| Chemical description: | Mercury sulfide, HgS |
| Visualization: | Visible microscopy, X-ray (bright/radio-opaque) |
| Identification: | XRF (Hg), Raman, SEM-EDS |