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Lapis lazuli, also known as just lapis, is a stone with one of the longest traditions of
being considered a gem, with a history stretching back to 7000 BC in Mehrgarh of
Indian subcontinent. Deep blue in color and opaque, this gemstone was highly prized
by the pharaohs of ancient Egypt, as can be seen by its prominent use in many of the
treasures recovered from pharaonic tombs. It is still extremely popular today. Lapis
is a rock and not a mineral because it is made up from various other minerals. To
be a true mineral it would have one constituent only.
The first part of the name is the Latin lapis, meaning stone. The second part,
lazuli, is the genitive form of the Medieval Latin lazulum, which came from Arabic
(al-)lazward, which came from Persian لاژورد lāzhward. This was originally a place-
name, but soon came to mean blue because of its association with the stone. The
English word azure, the Spanish and Portuguese azul, and the Italian azzurro are
cognates. Taken as a whole, lapis lazuli means "stone of azure".
Lapis lazuli usually occurs in crystalline marble as a result of contact
metamorphism. The finest color is intense blue, lightly dusted with small flecks of
golden pyrite. There should be no white calcite veins and the pyrite
inclusions should be small. Stones that contain too much calcite or pyrite are not as
valuable. Patches of pyrite are an important help in identifying the stone as genuine
and do not detract from its value. Often, inferior lapis is dyed to improve its color,
but these are often a very dark blue with a noticeable grey cast.
The finest lapis comes from the Badakshan area of Afghanistan. This source of lapis
may be the oldest continually worked set of mines in the world, the same mines
operating today having supplied the lapis of the pharaohs and ancient Sumerians.
Using this ancient source, the Indus Valley Civilization's artists used to make
beautiful carvings and traders used to trade them to distant places. More recently,
during the 1980s conflict with the USSR, Afghanistan resistance fighters is
assembled unexploded Soviet landmines and ordnance and used the scavenged
explosive to help mine lapis to further fund their resistance efforts.
In addition to the Afghan deposits, lapis has been found in the Andes near Ovalle,
Chile, where it is usually pale rather than deep blue. Other less important sources
are the Lake Baikal region of Russia, Siberia, Angola, Burma, Pakistan, USA
(California and Colorado), Canada and India.
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