Did you know ‘miniature’ didn’t originally mean something small? The word comes from a very specific job in the making of medieval manuscripts: the miniator was the person in charge of painting the first letter or heading of the text. This capital letter was an intricate illustration, depicting animals, people or leaves’ motives. The word ‘miniator’ comes from the pigment used in this first letter: minium or red lead (a lead tetraoxide).

Red lead is rare in nature and was usually fabricated. To make minium, you only needed an extra step when you were making white lead: first, you needed to put sheets of lead in a pot filled with vinegar, seal the pot and leave it in a warm place for a month. Then, you had to shake out the deposits around the sheets into a ceramic pot and place it on the fire. Stir the pigment constantly and you’d see it first turn a snowy white, and later an orange-red.

The product of painting with minium was called a ‘miniature’ and, over time, it would come to mean a small representation of something, but in the beginning both the job and the painting were named after this intense, although very toxic and with a tendency to turn black, pigment.

Minium is often confused with cinnabar (mercury sulfide) in medieval texts, sometimes their names exchanged. Cinnabar was more expensive and of a higher quality (equally toxic though). Another confusion is that while cinnabar refers to the mineral, the name of the pigment was ‘vermillion’, so knowing the pigments used just from the written sources is almost impossible.

The use of minium died out with the invention of printing, and with vermillion being more common from the 16th century onwards.