Alexandrite stone: characteristics, colors and the reason for its name in pictures – gemstones
Alexandrite stone, which is also known by the names “Alexander’s stone”, “the stone of the Caesars and the nobles” is one of the rarest natural colored gemstones discovered so far, which is characterized by a dazzling beauty equal to the beauty of ruby, sapphire and other famous gemstones that It may sometimes exceed it in beauty and value because it gives the wearer a unique look and an uncommon distinctive look. From a gemological perspective, the colors of alexandrite are the color variants of the element chrysoberyl, also known as cyclosilicate. Which despite its name “chrysoberyl,” which refers to beryllium aluminate, actually does not belong to the famous beryl group of minerals. Instead, it is classified as a separate mineral group.
But why is this alexandrite stone called, and what is the relationship of this stone with Alexander? Well, to answer this question we will inevitably have to delve into the history of this stone, let’s go back to the history of its discovery first, in which this credit is due to a French worker in the field of minerals and gem extraction called Nils Gustaf Nordenskiöld (born in the year 1866 and died in AD), made by Gustav in By discovering a stone similar to emerald but with different characteristics from one of the emerald mines located in the Ural Mountains region in Russia Near the Tokovaya River. This stone aroused the attention of scientists to be examined later and classified as one of the types of the group of chrysoberyl color variants that were affected by the element chromium.
Chemical formula | BeAl2O4 – beryllium aluminate oxide |
crystal structure | orthogonal rhombus |
Colors | Multiple |
hardness | 8.5 on the Mohs scale |
refraction | 1.746 – 1.763 |
Density | 3.70 – 3.78 |
cleavage | Good |
Transparency | transparent to opaque |
double refraction | 0.007 to 0.011 |
the sparkle | vitreous |
Radiation | Usually there is no |
Astrological month | June |
An alexandrite-studded ring
Thus, the interpretation of the name given to the stone is due to a legend that says that the Alexandrite stone was discovered on the same day that the next Tsar of Russia “Alexander II” reached the appropriate age to take over the rule. To that later it was considered the gemstone that symbolized the entire Russian Empire.
Alexandrite ore, chrysoberyl
Alexandrite stone has an amazing property referred to as the phenomenon of color change, also known as the “alexandrite effect” that can be observed under certain lighting conditions, usually represented by daylight variables and incandescent lighting. But what exactly is the feature of changing colors? and what do you mean? Quite simply, the property of changing colors “the Alexandrite effect” occurs in light of the change in the strength of light and the angle of its fall on the Alexandrite stone and the angle of its vision and presentation to appear in different colors whenever these conditions change, those colors are limited to green, red, orange, yellow. Alexandrite usually appears emerald green in broad daylight, while it appears raspberry red under incandescent lighting. It can also appear yellowish and pinkish. It is worth noting that there are types of Alexandrite that may show cat’s eye (cat’s eye) effects when it is specifically cut and shaped (unpolished). The phenomenon of color change results in the “Alexandrite effect” as a result of the intense absorption of light in the blue and yellow parts of the color spectrum.
What does changing the colors of a stone look like Alexandrite in light of changing lighting
There is a famous saying about the alexandrite stone that says that it represents (emerald stone by day, sapphire stone by night).
Alexandrite stone properties Chemical formula BeAl2O4 – beryllium aluminate oxide Crystal structure Rhombus orthogonal Colors Multi Hardness 8.5 on the Mohs scale
- Refraction 1. – 1.763 Density 3.464 – 3.464 Division
- J Dr Transparency Transparent to Opaque Double refraction from 0.007 to 0 . Sparkle vitreous Radiation
- Usually there is no Astrological month June
check up Alexandrite stone and its identification
Most of the chrysoberyl stones acquire their color from the presence of the iron element, but the reason behind the Alexandrite stone’s acquisition of its colors lies in the presence of traces from the element chromium. Thus, by performing spectroscopic analysis and testing, alexandrite stones can be easily distinguished from other similar stones.
It is worth noting that regular types of chrysoberyl may sometimes contain traces of chromium, but despite that, it is not It is classified as alexandrite as long as it does not have the discoloration we have indicated.
Sources and places of extraction of alexandrite stone
The main source of alexandrite stones dates back to a region in the Ural Mountains in Russia, which included A number of mines from which they were extracted and which, as a result of the intensity of the work in which they were carried out, have long been exhausted.
It was believed that for some time the mines worked in from the Ural Mountains were the only source of stone for Relatively large alexandrites, in particular, yen that weighs 5 carats or more, but recently in the year 1866 Large specimens have been discovered extracted from the state of Minas Gerais in Brazil.
What are the locations of the Alexandrite stone?
- Later Alexandrite stones were discovered and extracted in other regions and countries, including:
- Myanmar (Burma)
- Sri Lanka Tanzania
- India (Andhra Pradesh)
- (Madagascar)
- a For colors
- Natural Alexandrite Colors
- What are the colors of Alexandrite stone?
- Golden Yellow
- Green to yellow
- Brown
- the Red
- Teal
(Light green) (Violet) Red Violet on the side of the change feature Colors in Alexandrite stone, there are several natural types of it, each of which has attractive and wonderful colors that distinguish it, which it acquires through the different nature of the impurities inside it. For example, the green alexandrite stone acquires its color due to the presence of chromium impurities in its composition.
Thus, there are other types of alexandrite stones, including those extracted from mines located in Sri Lanka (Ceylon), which is characterized by gradient colors changing from khaki to brown due to the presence of impurities of various elements in its composition. While there is another type of these stones, originating from Zimbabwe, characterized by a few limited variants in color, usually dark in color with shades of purple. In addition, alexandrite stones extracted from Tanzania tend to be lighter in color, while the discoloration is medium and good. Its color is blue to violet. It is noted that the preferred and desirable Alexandrite stones are characterized by pure and clear colors in addition to the strong color-changing property in them.
Alexandrite quality factors
Quality Classification of Alexandrite Stones) The clarity of the rough alexandrite ranges from transparent to opaque before being cut, while alexandrite stones usually appear pure and clear immediately after being cut and polished, in addition to their distinctiveness. Glossy vitreous luster. Sri Lanka is known for producing the purest alexandrite which is often free from any visible inclusions whatsoever. It is noted that good-quality alexandrite stones may sometimes exceed the value of blue sapphires, emeralds and red rubies, especially stones that are larger than 1 carat. As for the size, it is rare to find alexandrite stones in large sizes and stones weighing more than three carats are extremely rare.
1- Color
The natural color of alexandrite turns green and bluish-green in Daylight and from red to bluish red in incandescent light. Its color saturation is strong to moderate. Stones too light do not reach the quality of color intensity seen in high-grade gemstones, and very dark stones lack brightness and appear almost black.
Sri Lankan alexandrites are usually larger than their Russian counterparts, but their colors tend to be to be less favorable. The greens tend to be yellow compared to the blue-green of Russian stones, and the color of Sri Lankan alexandrites is usually red-brown rather than purplish red. From Brazil is low in comparison
2- Purity Alexandrite stones tend to contain few impurities. There is a great increase in stones that are characterized by the quality of changing their colors and clarity.
When certain types of long and thin inclusions are located parallel to each other, they can create an additional phenomenon called the cat’s eye effect, which increases of the value of alexandrite.
3- Pieces Alexandrite is formed in various ways, including in the form of a cabochon and a triangle, where the stones of graduated cuts are concentric rows of parallel sides.
The multicolored alexandrite makes the cutting process very difficult, as the incisors must be directed at the stone to show the strongest change in color.
4- Carat weight
Most Alexandrite stones that are mined are of small size, weighing less than one carat. Sizes go up dramatically.