Where does the name Azure or Lapis Lazuli come from
According to the ancient Roman historian Pliny, in ancient times the name “Lapis Lazuli” was known as “sapphire” or sapphire. Lapis means stone and Lazuli means blue of the blue sky. Azure was called “azure” by the ancient Iranians, which the Arabs called azure because of their linguistic limitations. “Word” in the last part of this word is probably taken from “Bard” which in Bakhtiari language means stone
What is azure and what are its characteristics
Lapis Lazuli is a semi-precious stone with a bluish-blue color with a hardness of 5 – 5.5 on the mouse scale, which is relatively sensitive to heat, pressure, hot solutions, acids and solutions. Alkali is very sensitive. Azure stone does not crack and its fracture is irregular and its specific gravity, the higher the percentage of pyrite, varies between 2.7 to 2.9. Lapis lazuli is seen as opaque and its luster is glassy to waxy. It has no multicolor phenomenon and is idiochromatic, and its fluorescence is often neutral
The crystalline system of lapis lazuli cubic and dodecahedron in variable sizes in the form of veins, often found in the bed a few centimeters, among marble or irregular veins in limestone. Indigo blue is the best color and sky blue to green (which is confused with turquoise) are in the next categories
What is azure stone made of
Azure is not a mineral and is actually a metaphorical rock with the chemical formula Na, Ca (₆Al₆Si₆O₂₄ (S, SO) ₄) composed of several different minerals: mica, calcite (white impurities on it), diopside, hornblende, ogite, huinite and pyrite. Its main minerals are lazurite and sodalite (blue). Pyrite impurities, which are seen in the form of gold or bronze dots in this stone, have made it more visible. Now, if the amount of pyrite is high, azure can be seen as a green or opaque background. In Lapis Lazuli, Chile (north of Santiago) and Russia, they have a lower value due to the presence of prominent streaks and white spots of calcite
Synthetic azure stones
Mr. P. Gilson and others have made efforts to produce synthetic azure stone, although many jewelers do not consider it a basic center. Gilson Lapis Lazuli’s specimen is very similar to its natural counterpart. In 1954, artificial glass ores such as spinel were painted with cobalt oxide and sold as lapis lazuli, which is easy to detect because it does not contain any inclusions or substances such as pyrite
Stones that you may confuse with natural azure
Azure can be confused with stones such as lazolite, sodalite, azurite, jasper blue or domertyrite. Today, stones often dye low-quality azure, which depending on the quality of the resin used and its processing method may fade or remain unchanged over time
For example, Dolomite (Mountain Jade) or Jasper or Howlite marbles are painted with blue resin and polished with oil. On the other hand, some eat the azure and squeeze it together with plastic
In German Neukrish, jade-brown gray powder is melted in a blue process and marketed as Swiss lapis lazuli. Others use pyrite to beautify this stone
Also, sometimes there are different names of this stone in the market, such as: Swiss Lapis (painted jasper or chalcedony), German Lapis (painted jasper), Canadian Lapis (the same as sodalite), so you should not confuse them with lapis lazuli
How to distinguish the original azure from the counterfeit
Natural azure is always cold when you hold it in your hand, but artificial and plastic stones heat up with a little holding
Wet a cotton ball with acetone and hit the rock surface. This material dissolves the artificial color in itself
Check the color difference in the cracks of its surface with the magnifying loop
As a destructive test for azure reconstructed with plastic material, the hot tip of the metal rod gives off an unpleasant plastic odor. These specimens also sink by pressing under the tooth
Be careful when buying azure that has a uniform color without streaks or spots and is very colorful and looks like artificial colors
With the Chelsea Filter Gemological Tool, you can distinguish original azure from synthetic and laboratory. Under Chelsea filter, natural lapis lazuli reflects a faint reddish-brown light, while the synthetic type reflects bright red light
Tips to remember when buying natural azure
When there is too much white in the stone, it is classified in the cheap calcite class
When the color of the stone you want is dark blue-gray, it is probably not lapis lazuli and it is sodalite
They usually paint low-quality sodalites and sell them as azure! Many imitation lapis lazuli are found in Taiwan
Artificial azure specimens made of golden dots are not visible, but are less common in Gilson synthetic specimens
Physically, natural azure rough has a light blue sand color on the glazed porcelain surface. If you halve it, you will not smell very pleasant (due to sulfur)
Obtained a guarantee from the seller that in case of a negative answer, the gemology laboratory will take it back
Where are the azure quarries located
There are very few azure mines in the world, and today in Badakhshan, Afghanistan, the Kokcheh Valley in the Kranomunjan region, as well as the western Hindu Kush mountains near the source of the Amu Darya River, are among the best azure species in the world still extracted by traditional methods. Afghan lapis lazuli has been considered since 6,500 years ago during the Achaemenid period, which was part of Iran
Pakistan in the Chaga Mountains at Bibi Dick, 35 km north of Dalbandian near the Afghan border, Lake Baikal in western Russia where Lapis Lazuli contains Dolomite marble, the Pamirs, South America, the Sinai Peninsula and parts of Iran. Other sources of lapis lazuli are
What is the best type of azure stone
In general, the deeper the blue lapis lazuli stone, the higher the value of one hand and without cracks and golden streaks of pyrite. Khajeh Nasir al-Din al-Tusi, in his book Tansukhnameh Ilkhani, writes in mentioning the attributes of good azure: Azure in which gold can be seen and the smoother and more colorful and the less white it is, the better, it is necessary to mention books Old people have always preferred Badakhshan azure stone to different types of azure stones
Today, Afghan or Persian lapis lazuli has a bluish-purple color and is classified as one of the best types of azure with a small amount of pyrite. The Russian or Siberian type has different blue colors and some amounts of pyrite and calcite. There is another example called Chilean, which has green dots as well as white calcite as a tree
