Lapis Lazuli
Lapis Lazuli is a semi precious stone formed during the metamorphosis of chalk into marble. It has a cubic crystal system, and is in the mineral class of lattice silicate.
Lapis Lazuli has been prized since antiquity for its intense blue color, and has been mined since 7th Millennium BC from a number of mines in the area of Afghanistan.
Lapis is the Latin word for "stone" and lazulī is the genitive form of the Medieval Latin lazulum, which is taken from the Arabic لازورد lāzaward, itself from the Persian لاجورد lājevard. It means "sky" or "heaven".
Beads of this semi-precious stone have been found at a number of Neolithic burials as far from Afghanistan as Mauritania, and it was also used in the funeral mask of King Tutankhamun.
At the end of the Middle Ages, it began to be exported to Europe, where it was ground into powder and made into ultramarine, the finest and most expensive of all blue pigments, which was used by some of the most important artists of the Renaissance and Baroque.