Lapis Lazuli

Man first discovered lapis lazuli almost 7,000 years ago. It has been found in ancient civilizations such as Egypt, Persia, Greece, Rome and the Middle East. 

It’s an easy, workable stone, so it’s not used only in jewelry, but also carving, mosaics, ornaments. It is also processed to make blue pigments for make-up and painting.

In Egyptian culture, this stone has an important connection with religion. Archaeologists found abundant amulets and talismans made in Lapis.

Its vivid blue color made it an important component of some European masterpieces. The frescos of some important medieval churches in Italy were made using the blue pigment made from lapis lazuli.  It is pretty impressive if you consider that at that time the Lapis was really expensive and was available only from one far source: Afghanistan.

Lapis lazuli is not a gem, but a rock, which means that it is an aggregate of several minerals, including but not limited to: Lazurite, Calcite and Pyrite. The quality of the stone is determined by the percentage of these three minerals. For example, if the calcite matrix is too present in the stone, it looks white and therefore less appealing.

Lazurite

pyrite

calcite

The presence of the pyrite flakes makes the stone look like a sky full stars, and this is the reason why people believed that the stone unleashed peace and  relieved stress. Kings and queens used it in the past as a powerful status symbol; it was considered a piece of heaven given to men by the gods.

The top quality color is a violetish blue with no-visible calcite and some gold looking pyrite flecks. The presence of an excess of calcite or pyrite can lower the quality of the stone and make it look greenish and less valuable. Its hardness is 5 to 6 on the Mohs scale.

It can be found in different shades of blue, depending on the other minerals in the aggregate.

On Earth, there are not many Lapis mines: the finest quality is found in Afghanistan, the oldest source, but it is found also in Chile and Russia.

Because fine-quality Lapis stones are highly priced, treatments are common, but not stable, which makes the treated stone less valuable than untreated one. The dyeing treatment is used frequently; it’s used to enhance the blue coloration and cover the white coloration caused by the calcite but can be rubbed away with acetone. Usually after dyeing, it is also impregnated with wax to protect the stone and make it appear shiny.

Gilson 

Lapis imitations are plenty and are old as lapis itself. Glass, plastic and ceramic are very common in the market, they are manmade at a low cost.  Another manmade material created just to imitate Lapis is the Gilson Imitation Lapis Lazuli, which apparently looks just like the original, but is actually very porous. Is Its hardness is 3 on the Mohs scale and the luster is dull. The color is perfectly even and the pyrite flakes appear like sprinkles on the surface. Other substitutes are Chalcedony and sodalite.

Until the 1950s it was one of the December birthstones, so it can be used as a good alternative to Tanzanite and Turquoise for people who were born in that month.