About the blog: What Things Are Made Of
AMERICA'S GLOBAL DEPENDENCY FOR NEARLY EVERYTHING
Saturday, March 27, 2010
Fragments of the starry firmament
Grinding the blue rock, mixing it with waxes and oils, and processing in a lye solution yielded natural ultramarine pigment.
Lapis lazuli’s rarity made for notable expense (greater than gold) in making ultramarine pigment. In European monasteries, highest quality ultramarine was used only on the most important, prestigious artworks, for the robes of Mary and the Christ child. By the 1820s, a synthetic version was devised, and reliance on Afghan sources, the most significant in the world, waned.
The rock lapis lazuli contains multiple minerals, with the blue color coming mostly from two complex sodium-calcium aluminosilicates, lazurite and sodalite.
Even after synthetic dyes became the rage in the 1850s and 1860s, the natural material still served special purposes such as printing postage stamps. Stamp collectors who own blue-tinted U.S. postage stamps from the 1860s (such as the 3¢ ultramarine locomotive in the 1869 pictorial issue) probably have some microscopic bits of Afghan lapis lazuli.
The word ultramarine means “beyond the sea,” whence came lapis to Europe. Pliny the Elder gave the beautiful stone a more admiring description, calling it “a fragment of the starry firmament.”
Photo of polished slab of lapis lazuli, from Wikipedia under the Creative Commons Attribution ShareAlike 3.0 License