Lazulite is famous for its deep blue variety called lapis lazuli.

Chemical Formula: FeS2
Class: Iron sulfide
Hardness: 6-6.5
Coloration: pale brass yellow

How to identify it/Unique Characteristics or Properties: Lazulite has been mined as a precious mineral for at least 5000 years, most famously for its deep blue variety called lapis lazuli (with other minerals). Lapis lazuli was famous because it is so brightly colored and yet not a crystal so could be used to add color to and entire room.

Lazurite does come in crystal form, as dodecahedrons. It also comes in other colors than just blue, and is in fact often translucent. The variety pictured above is embedded in Mica.

Where to find it in…

The Northwest: Jackson County, Oregon
Other: Quite rare, lazurite is only found in quantities in Siberia and in the Kokcha valley in Afghanistan.
Past Uses: Lapis lazuli was cut and used as an ornamental gemstone for millenia. Lazurite has also been ground up and used as a blue pigment, ultramarine.
How it was Made: Pyrite forms in many different ways, but primarily in hydrothermal vents and in volcanic flows.
Interesting Facts: Was famously used in everything from Babylonian and Egyptian, to Roman decorations.