Lapis lazuli is composed primarily of the mineral lazurite, but commonly contains calcite and pyrite. The darkfield photomicrograph below illustrates a thin section of a rock containing lapis minerals photographed with a compound microscope using a 10x objective.

The name "lapis lazuli" means blue rock and the mineral is usually found in a brilliant blue with violet or greenish tints. The rich blue color derives from sulfur-containing compounds intertwined in the crystalline lattice. This beautiful mineral was first mined in Afghanistan thousands of years ago, and is very commonly used for making jewelry in the middle east and throughout the world. The best source for lapis is the mountains in remote Afghanistan, although the mineral is also found in Chile and in smaller quantities in Russia and other countries.