The walls of Pompeii are still red. After 2,000 years buried under volcanic ash, the frescoes uncovered in the 18th century retain the same intense scarlet they had when Vesuvius erupted in 79 CE. That red is vermilion, made from cinnabar, a mercury ore that the Romans mined in Spain and shipped across the empire. The pigment was expensive, toxic to produce, and so associated with wealth and power that Roman officials fixed its price by law. Pliny the Elder wrote that vermilion was so precious that it was kept under lock and key during festivals to prevent theft. The walls of Pompeii's Villa of the Mysteries, covered in this red from floor to ceiling, are a display of conspicuous consumption that has outlasted the empire that produced it.
Vermilion is a red pigment composed of mercury sulfide (HgS). It occurs naturally as the mineral cinnabar, which has been mined and ground into pigment for at least 9,000 years. The pigment can also be synthesized by combining mercury and sulfur, a process known since antiquity. Natural and synthetic vermilion are chemically identical, and both produce a vivid, slightly orange-red that is among the most saturated reds available in any medium. The pigment is toxic because it contains mercury, which can be absorbed through the skin, inhaled as dust, or ingested. Despite this, vermilion was used continuously in painting, lacquerwork, manuscripts, and cosmetics from prehistory until the 20th century, when it was gradually replaced by cadmium reds and other synthetic alternatives.
This entry covers the history of vermilion, its production methods, the artists who used it, and the conservation challenges it poses today.
What Is Vermilion and Where Does It Come From?
Vermilion is mercury sulfide, a chemical compound with the formula HgS. In its natural form, it is the mineral cinnabar, a heavy, reddish-brown stone that forms near volcanic activity and hot springs. The largest and most historically significant cinnabar deposits are at Almaden in Spain, which has been mined for over 2,000 years and was the primary source of mercury for the Roman Empire and later for European industry. Other major sources include the Monte Amiata district in Italy, the Huancavelica deposit in Peru, and deposits in China, particularly in Guizhou and Hunan provinces.
Natural vermilion is made by simply grinding cinnabar into a fine powder and washing it to remove impurities. The grinding process is hazardous because it releases mercury dust. Synthetic vermilion is made by heating mercury and sulfur together in a sealed vessel. The two elements combine to form vermilion, which sublimes and deposits on the vessel walls as a red crystalline powder. This process, described in European alchemical texts from the medieval period, was also developed independently in China, where synthetic vermilion was used in lacquerware from at least the Han Dynasty (206 BCE to 220 CE).
A 2024 study published in the Journal of Archaeological Science identified the earliest use of cinnabar in the western Mediterranean at the Neolithic settlement of La Marmotta in Lazio, Italy, dated to the seventh millennium BCE. The study found cinnabar on ornamental items including lithic and shell beads, distinguishing it from ochre through physicochemical analysis. This pushes back the known use of cinnabar as a pigment in the region by several millennia. Read the study at ScienceDirect.
Origins and History
The earliest known use of cinnabar as a pigment comes from a painted plaster skull from Kfar HaHoresh in Israel, dated to the 9th millennium BCE. In the Copper Age, cinnabar was used extensively in Iberia for funerary purposes. A 2024 study published in the Journal of Archaeological Method and Theory examined mercury exposure in 170 samples from 70 individuals at the Copper Age mega-site of Valencina in southwestern Spain, dated between 2900 and 2650 BCE. The study found abnormally high mercury levels in individuals buried in elite tombs, caused by the manipulation of cinnabar for body decoration, object decoration, and possibly direct consumption. The researchers concluded that Valencina represents "the most intense and prolonged case of exposure to mercury recorded in human history." Read the full study at Springer Nature Link.
In China, cinnabar has been used since the Neolithic period. The pigment was ground and mixed with lacquer to produce the deep red lacquerware that became one of China's most distinctive art forms. Cinnabar was also used in Chinese painting, particularly in imperial documents and seals, where the red pigment was associated with authority and divine mandate. The word for cinnabar in Chinese, "dan," appears in the term "dantian," meaning "cinnabar field," a concept in Chinese internal alchemy referring to the body's energy center.
In Rome, vermilion was used in frescoes, particularly in the houses of the wealthy. A 2024 study in the Journal of Archaeological Science: Reports analyzed cinnabar from Roman wall paintings in Ephesus (modern Turkey), using lead isotope analysis to trace the pigment's provenance. The results suggested that the cinnabar originated from the Almaden mining district in Spain, confirming the long-distance trade networks that supplied Roman painters. Read the study at ScienceDirect.
In the Americas, cinnabar was used by pre-Hispanic societies for millennia. A 2025 study published in PLOS ONE used mercury isotope analysis to trace cinnabar pigment from archaeological sites across the Andes to the Huancavelica deposit in Peru, confirming that this single source supplied cinnabar for much of pre-Hispanic South America. The study analyzed 97 pigment specimens from museum collections and excavations, demonstrating that mercury isotopes can geochemically trace cinnabar ore. Read the study at PLOS ONE.
Key Artists and Paintings
The Pompeian Fresco Painters (1st century BCE to 79 CE)
The Villa of the Mysteries in Pompeii, dated to around 60 BCE, features walls covered in a deep red ground that is predominantly vermilion. The pigment was applied in fresco, meaning it was painted into wet plaster and became chemically bonded to the wall surface. This is why the red survives: the pigment is part of the wall, not a layer on top of it. The same red appears in the House of the Vettii and the House of the Tragic Poet, always in the most important rooms.
Titian (c. 1488-1576)
Titian used vermilion in the robes of figures in several major altarpieces. In the Assumption of the Virgin (1516-1518, Frari Church, Venice), the red robes of the apostles below are painted with vermilion, creating a chromatic contrast with the ultramarine sky above. Titian layered vermilion with translucent glazes of cochineal lake to produce reds of extraordinary depth and warmth.
Vermeer (1632-1675)
Vermeer used vermilion in small but significant areas of his paintings. In The Art of Painting (c. 1666-1668, Kunsthistorisches Museum, Vienna), the model's red stockings and the red curtain are painted with vermilion. The pigment's opacity and brilliance made it ideal for these small, intense accents of color. Vermeer typically mixed vermilion with white lead to create the pinkish flesh tones in his figures' faces.
Mark Rothko (1903-1970)
Rothko used vermilion in several of his color field paintings from the 1950s and 1960s. Red on Red (1959, Whitney Museum of American Art) uses layers of red pigment including vermilion to create a pulsing, atmospheric field. Rothko's use of vermilion alongside cadmium reds and alizarin crimson produced the deep, saturated reds that characterize his most powerful paintings.
Chinese Lacquer Artists
Chinese cinnabar lacquer, produced from the Han Dynasty onward, uses ground cinnabar mixed with sap from the lacquer tree. The lacquer is applied in dozens or hundreds of thin layers, then carved to create relief designs. A 2023 review published in Archaeological and Anthropological Sciences traced the use of cinnabar in Chinese lacquer production and noted that the pigment's stability in the lacquer matrix is exceptional: objects from the Han Dynasty still retain their original red color. Read the review at Springer Nature Link.
How to Spot Vermilion in a Painting
Vermilion is a warm, slightly orange-red. It is more opaque than organic red lakes like cochineal or madder, and it has a distinctive crystalline quality under magnification. In oil paintings, vermilion tends to retain its saturation better than organic reds, which fade over time. If you see a red in a Renaissance painting that has held its color for 500 years without fading or turning brown, it is likely vermilion.
One problem with vermilion is that it can blacken over time. The blackening is caused by the conversion of red mercury sulfide to black metacinnabar, a process triggered by light exposure and environmental conditions. This is why some reds in old paintings appear dark brown or black rather than the original scarlet. The National Gallery in London has documented this phenomenon in several paintings, including works by Rubens where vermilion has darkened significantly.
Vermilion belongs to the family of inorganic pigments. Its closest modern replacement is cadmium red, which provides a similar opacity and saturation without the toxicity of mercury. Ochre provides a cheaper, less saturated red that has been used since prehistory. Organic reds like cochineal lake produce more translucent, cooler reds. For more on the broader context of pigments in painting, read our entry on oil painting, or explore our post on chiaroscuro and dramatic contrast to see how red pigments contribute to light and shadow.
See Vermilion in Person
The most spectacular surviving vermilion is in Pompeii. The Villa of the Mysteries, now part of the archaeological site near Naples, retains its full red walls after 2,000 years. The National Archaeological Museum in Naples holds many frescoes removed from Pompeii and Herculaneum, including panels with intact vermilion surfaces. In Rome, the House of the Vettii (reopened in 2022 after restoration) displays extensive vermilion frescoes.
For vermilion in easel painting, visit the Kunsthistorisches Museum in Vienna to see Vermeer's The Art of Painting, or the Frari Church in Venice for Titian's Assumption of the Virgin. For Chinese cinnabar lacquer, the Metropolitan Museum of Art in New York and the Palace Museum in Beijing hold extensive collections. For more on the pigments that shaped painting, read our entries on ultramarine and lead white, or explore our guide to how to read a painting.
