What is Lapis Lazuli?

Lapis lazuli is a translucent stone, of which lazurite is the main component. Its other components include calcite and pyrite. While its dark blue color comes from lazurite, the golden patterns on the stone are due to the pyrite inclusions. The prize of lapis lazuli depends on its content. A moderate amount of pyrite, for example, adds value to lapis lazuli as it keeps a good balance between the goldenness and blueness of the stone. On the other hand, a high calcite ratio is undesirable for it decreases the value of lapis lazuli.

The best lapis lazuli is found in Badakhshan, a historical region located in northeastern Afghanistan, as it includes no calcite. The mines here began to be exploited in the Neolithic Period and their stone was exported to distant regions such as Egypt and Mesopotamia. The ancient Egyptians favored lapis lazuli so used it as the raw material for decorative objects while the Sumerians, Assyrians, and Babylonians utilized the stone for making seals as well as ornaments.

Lapis lazuli can be used in its powder form, too. If you ground the gem, it will serve as a natural pigment called ultramarine. This method of producing an impressive blue hue was adopted by the Renaissance and Baroque painters. The most famous application of ultramarine in painting is the blue headscarf depicted in Vermeer’s portrait Girl with a Pearl Earring. Not surprisingly, lapis lazuli is no more used as a pigment source as there are way cheaper methods to produce dyes today.

Image: Vermeer's painting Girl with a Pearl Earring (retrieved from Ivan Snowpaw, CC BY-SA 4.0 <https://creativecommons.org/licenses/by-sa/4.0>, via Wikimedia Commons).

References

“Lapis Lazuli.” International Colored Gemstone Association, https://www.gemstone.org/lapis-lazuli. 

“Lapis Lazuli.” Wikipedia, Wikimedia Foundation, 16 Aug. 2022, https://en.wikipedia.org/wiki/Lapis_lazuli.