Definition
Mohs scale hardness 8.5
While alexandrite comes from many parts of the world, truly high-quality gemstones have certain characteristics and are "regarded as one of the rarest and most precious gemstones. According to well-known labs, the best duotone colors for alexandrite are a vibrant grass green under daylight and fluorescent lighting, and an intense raspberry red under incandescent lighting. Many modern sources often use "emerald by day, ruby by night". Romanticize the color of alexandrite. Alexandrite is the birthstone for June. Alexandrite is also a 55th wedding anniversary gemstone. In fact, alexandrite surpasses almost all other known gemstones in terms of rarity. Most high-quality alexandrite gemstones are not readily available anywhere. However, we have many alexandrites for sale. The more pronounced the color change, the more valuable the alexandrite. Therefore, some alexandrites are very expensive.
- GUB- Gübelin Gem Laboratory: Alexandrite is a chrysoberyl whose dominant hue varies from solar to incandescent.
- GRS- GemResearch Swiss Lab: Alexandrite: is a color-changing chrysoberyl that contains chromium.
- AGL- American Gemological Laboratories (AGL): Alexandrite is a type of chrysoberyl whose primary hue changes dramatically under different lighting conditions.
- Christian Dunaigre (CD): Alexandrite is a chromium-containing color-shifting chrysoberyl (color-shifting: the dominant hue is different in the daylight than under incandescent lighting). Gemological Institute of America (GIA): Any color change (not a change) will turn a chrysoberyl into an alexandrite.
History
The rare alexandrite, which has a long history of association with Russian monarchy, was given that name in 1833 after Russian Czar Alexander II when it was found in the Ural Mountain range in Russia.
According to gem annalist Richard A. Wise, Kokovin was the Russian Ural Mountain Mine Manager around the 1800s. ( Wise, 2016). Wise’s reference to Kokovin, albeit brief, is to our knowledge, one of the only publications that one person credits for alexandrite’s discovery. Wise’s source for this fact is the book “ Russian Alexandrites. ”
The detection of the first Russian Alexandrite itself has divergent wells. This is indeed clear from GIA’s own characterization of Alexandrite’s origin “ discovered in 1830 by cornucopia in the Ural mounts of Russia ”( GIA, 2018)( Emphasis appended).
The fact that an institution like GIA exclusively uses “ cornucopia ” for credit detection further shows the nebulosity behind laying someone for the new variety designation. Besides the difficulty in narrowing the exact existent who booby-trapped it, an alexandrite’s trimmer type trait would further complicate realizing its true identity. This complication is due to the fact that Chrysoberyl( the mineral Alexandrite falls under) had been formerly discovered previous to 1830. thus, in order to discern chrysoberyl from beryl or emerald, an alternate person( besides the factual cornucopia) would have to have some mineral knowledge. It appears that after relating it as chrysoberyl, and seeing that the chrysoberyl passed color revision, the question arises as to who had the eureka moment of coining the new varietal name. given away these refined portions, you can imagine laying a single existence as responsible for discovering the first alexandrite in Russia to be tricky. On the one phase, one could enunciate that changing the mineral itself would mean credence for detection. On the other phase, some might enunciate that taking the way to determine that it was exclusively chrysoberyl with prominent color would warrant credence.
Origins
The main sources for Alexandrite around the world
Russia
The Ural Mountains are thought to be the origin of Russian Alexandrites. Today, it is quite challenging to find Alexandrite above 1 carat in gem grade from Russia. Any Alexandrite included in Russian rough is often of low grade, and the rough is typically Emerald in color. The phrase "Emerald by day, Ruby by night" is frequently used to describe Alexandrites, and is probably alluding to Russian Alexandrites that exhibit such striking color variations. Blue-green Russian Alexandrites can be mistaken for anything. Old cutting or faceting may help identify the provenance. Additionally, the inability to find inclusions will make it challenging to identify Russian content.
India
Indian Alexandrites are recognized for their distinctive, bright green hue in daylight. Most Indian Alexandrites from the Orissa mine, according to some of our contacts in the Indian gemstone mining industry, are tiny melee stones (less than 0.5 carats). The color of daylight typically has a deeper, grassier green tone. The purple of the incandescent hue is often not as striking. In actuality, the saturation of the purple may be defined as medium to light. Despite the low output, blue-green to deep purple Alexandrite from India occasionally appears.
Sri Lanka
It should come as no surprise that the renowned exotic nation, known as the "Island of Gems," produces Alexandrites.
In the sunshine, Alexandrites from Sri Lanka often appear yellowish-green. Additionally, Ceylon Alexandrites are often bigger than Alexandrites from other nations. Despite being bigger, they usually don't change colors much. The few bigger size Alexandrites from Sri Lanka that have a noticeable color shift are still quite rare. We have learned from our mistakes how tricky it is to identify from Madagascar and Ceylon Alexandrites. The material is actually cut in Sri Lanka by local vendors who import the raw alexandrite from Madagascar.
Tanzania
Tanzanian Alexandrites are still hard to find. Due of the obvious similarities between Madagascar and Brazil in this origin's traits, laboratories have trouble categorizing it. In our experience, Alexandrites from Tanzania typically exhibit a brighter Mediterranean Bluish-Green shade in daylight. The Tanzanian Alexandrites we have seen almost invariably exhibit a striking color shift under incandescent light.
Madagascar
Some of the best Alexandrites on the market right now, which may appear blue-green when exposed to light, are from Madagascar. Alexandrites from Madagascar that are of lower grade can have a brown coloration. The highest-grade Alexandrites from Madagascar will always have a pronounced green hue. A blue tone is best for modifying the clarity of the green. Additionally, the purple will have a pink-purple intensity that is comparable to the best Alexandrites from other areas.