The beautiful in paintings from the Renaissance are thanks to the blue lapis lazuli, the opaque blue gem material that was the secret ingredient in ultramarine, the valuable pigment that all the old masters used to capture the rich blues of the sea and sky and the robes of the Virgin Mary. The color was not duplicated by nay other substance until 1834 but even now, some argue there is no substitute: unlike other pigments ultramarine centuries old still glows with rich color today.
As befits a gem that has been international currency for millenia, the name lapis lazuli is melange of languages. From the Latin, lapis means stone. From Arabic azul means blue.
Lapis lazuli is still mined at the deposits of the ancient world in Afghanistan. Today, lapis lazuli is also mined in Chile. Small quantities are also produced in Serbia, in Colorado in United States, and in Myanmar.
Lapis lazuli is somewhat porous and should be protected from chemicals and solvents. Lapis is not very hard, should be protected from other jewelry when stored to avoid scratches. Clean with mild dish soap: use a toothbrush to scrub behind the stone where dust can collect.