The most sacred blue in Renaissance painting was mined in Afghanistan
Ultramarine — the blue of madonnas, summer skies, and the Virgin's robe — cost more than gold. It came from a single mountain range, and grinding it only produced gray.
Medieval and Renaissance painters who wanted the truest blue had to begin in the mountains of Badakhshan, in what is now northeastern Afghanistan. That is where lapis lazuli was quarried, the only known source for centuries. When the stone arrived in European workshops, artists found that grinding it directly turned it a disappointing ash gray — the blue was locked inside waxy impurities.
The extraction process, called pastello, required kneading powdered lapis with wax, oils, and resins, then working the mass in warm water until the pure blue particles separated out. It was slow and expensive enough that contracts often specified exactly how much ultramarine a painter was allowed to use per panel. The blue in a Virgin's robe was an economic signal as much as a spiritual one.
Philip Ball traces this logic throughout the history of color: pigments didn't just express what artists saw, they shaped what artists could attempt. When synthetic French ultramarine arrived in 1826, the same blue became almost free — and the Virgin's robe stopped meaning what it once had. The color was the same. The scarcity that gave it weight was gone.