Tips for stone care

What is the difference between natural alexandrite and artificial one?

One of the frequently asked questions is: “I’m looking to buy alexandrite. How can I independently verify that alexandrite is natural and real? There are few possible answers to this question. If the stone is accompanied by a certificate of gemological examination (colloquially referred to as a certificate), one or more (not uncommon for expensive stones) issued by internationally respected and recognized laboratories, then there is actually nothing to be convinced of. It is enough to check in the laboratories themselves whether such an examination certificate was issued, and that’s all. If the stone is offered without a gemological examination certificate, then. Not only a non-specialist, but even a specialist, only in the case of the most “egregious” imitations, is able to establish the truth by eye, without tests. Such “blatant” imitations are cubic zirconia and heavy metal synthetic garnets with a color-changing effect, and, to a lesser extent, synthetic sapphires with a color-changing effect. The simplicity lies in the fact that neither one, nor the other, nor the third material has typical alexandrite shades. In other cases, the answer to the main question will be disappointing: on your own, without tests – NO WAY. The information below is not intended for professionals; they, professionals, already know this all. But for those who like to solve gemological problems, for jewelers and sellers who understand their responsibility, who are willing and able to master the basics of gemological tests, and for buyers who want the same, what is described below may, if desired and necessary, prove useful. So: alexandrite is a variety of the mineral chrysoberyl enriched with chromium impurities. The main identification features of natural alexandrite: Refractive index: 1,746 – 1,755; +0,004/-0,006
Birefringence value: 0,008-0,010
Optical character and sign: Birefringent biaxial positive, rarely biaxial negative
Specific gravity: 3,71 – 3,75
Pleochroism: Strong, pleochroic colors Green, dark red, orangish yellow
Reaction to ultraviolet light: from complete inertness to medium fluorescence. Fluorescence color in both ultraviolet ranges (long-wave and short-wave) is red
Reaction to magnet: from complete inertia to weak.
Color range: daytime colors – strongly bluish green, green, yellowish green; artificial light: orange-red, red, reddish orange, Carnot purple or purplish red, reddish purple, purple-red. Basic principles and methods of distinguishing alexandrites and imitations: – Cubic zirconia. Completely unnatural colors of cubic zirconia, specific gravity (5,60 – 6,00). – Heavy metal synthetic grenades. Completely unnatural colors of such garnets, optical character (single refractive, clearly visible in a polariscope), specific gravity (7,0+). – Jewelry glass. First of all, the optical character, the polariscope will show a typical amorphous reaction for glass, the absence of pleochoroism (dichroscope). In terms of specific gravity and average refractive index, modern jewelry glasses may fall within the range of alexandrite, so you cannot completely rely on these parameters. – Andalusite. Natural andalusite is quite difficult to confuse with alexandrite even with a simple external examination. However, some low quality alexandrites can appear similar to andalusite in daylight. It is not difficult to distinguish andalusite from alexandrite by some basic characteristics – refractive index (1,634 – 1,643; +0,005/-0,005), specific gravity 3,13 – 3,21), typical spectrum. – Garnet with color changing effect. Externally, some color-change garnets, especially from the Nandagale deposit, are completely indistinguishable in color and behavior from alexandrite. However, large garnets are almost never “passed off” as large alexandrites due to their own high cost and the greater rarity of the garnets themselves. Small (up to 1 kt) garnets “mimic” alexandrite are not so rare. It is not difficult to distinguish garnet from alexandrite by some basic characteristics – often by the average refractive index (1,760; +0,020/-0,018), but it is not easy for small stones by specific gravity 3,78 – 3,85). The most reliable identifier is the optical character and associated properties – garnet is isotropic, that is, monorefractive, does not have pleochroism and birefringence. Most garnets with a color changing effect stick to a strong magnet (up to 2-3 kt in weight, larger ones move confidently, or the magnet itself, if small, moves towards them). – All types of corundum with a color-changing effect, natural and synthetic, are easily distinguishable by all main characteristics – by refractive index (1,762 – 1,770; +0,009/-0,005), specific gravity (3,95-4,10), optical character ( birefringent uniaxial negative), according to the typical spectrum. Natural alexandrite effect sapphire does not have the daytime alexandrite color. – All types of spinels with a color-changing effect, natural and synthetic, are also easily distinguishable by all the main characteristics – by refractive index (1,700 – 1,735), specific gravity (3,57-3,70), optical character (isotropic, unirefringent, not has birefringence (anomalous birefringence is an extremely rare exception to the rule) and pleochroism), according to the typical spectrum. Natural spinel with color change effect does not have alexandrite colors. – Synthetic alexandrite. The most difficult case! If you are very lucky, you can limit yourself to fairly simple tests. Natural alexandrite can sometimes react poorly to a strong magnet. Synthetic alexandrite is completely inert to magnets. Fluorescence – Synthetic alexandrite can exhibit strong red fluorescence, the same as natural alexandrite in both UV ranges, but stronger. It’s just not easy to understand and distinguish the strength of fluorescence. BUT! Some synthetic alexandrites have the remarkable property of fluorescent brightly in both UV ranges with an orange color. If such a reaction is observed, the answer has been definitely found! If neither magnetic properties nor fluorescence help, then the only relatively simple standard gemological method is a thorough examination of the stone under a microscope. In this case, the microscope must be either gemological or adapted for solving problems in gemology (the mandatory presence of a dark-field condenser and the possibility of using diffraction and 2 polarization filters). Photos and comments from Edward Gubellin and John Koivula’s Atlas of Inclusions, Volume 2, pp. 401-405 are used to illustrate what to look for under the microscope when identifying synthetic alexandrite. 1. Primary flux inclusions. The crystalline structure of the flux and narrowed, as if “shrunken” gas bubbles. 30x, dark field, fiber backlight. 2. Primary inclusions of crystalline flux and secondary inclusions of “fingerprint” type flux. 15x, dark field, fiber backlight. 3. Flux-grown alexandrite contains triangular and hexagonal platinum inclusions, as well as small flux particles. 20x, dark field, fiber backlight. 4. The synthetic origin of flux-grown alexandrite is clearly revealed by platinum inclusions of various forms. 50x, dark field, fiber backlight. 5. Platinum inclusions in synthetic flux-grown alexandrite exhibit curious “skeletal” shapes. 25x, dark field, fiber backlight. 6. Straight parallel growth zones can be found in flux-grown synthetic alexandrite. 10x, dark field, shading. 7. Growth zones in flux-grown synthetic alexandrite may also appear as broken lines and exhibit layering. 15x, dark field, shading. 8. The same lines in the same stone can completely change their appearance even with the slightest change in the orientation of the stone (rotation). 15x, dark field, shading. 9. The texture, similar to tree bark, clearly reveals the synthetic nature of alexandrite. Dark field, shading, 12x. 10. Twinning in synthetic flux-grown alexandrite. Can be seen in polarized light. Polarized light, 10x. 11. Feature of twinning in synthetic alexandrite: when the analyzer is rotated 90 degrees, the manifested pleochroic shade of the twinning sectors changes. Polarized light, 10x. 12. This 3,31 carat synthetic alexandrite (cat’s eye) made using the Czochralski method exhibits the typical light distribution effect of a cloudy “colostrum” type spot with a conical shape. 13. Wave-like color-growth zones are the most reliable diagnostic indicator of the synthetic nature of alexandrites with a cat’s eye effect grown using the Czochralski method. Transmitted light, shading, 30x. 14. In the oblique reflected light of fiber-optic illumination, wavy color-growth zones in synthetic Czochralski alexandrite (cat’s eye) look like a series of laminated layers, light zones are translucent, dark ones are almost opaque. Fiber optic backlight, 30x. 15. In some synthetic alexandrites (cat’s eye) Czochralski, one can observe internal linear defects that look like a strictly straight thin zone of a deeper dark shade and are always located strictly perpendicular to the “standard” color-growth zones. Bright field, passing diffuse color, 35x.
16. Most gas bubbles in synthetic Czochralski alexandrite have an “irregular”, irregular, most often elongated shape. Bright field, shading, 10x. 17. Irregularly shaped gas bubbles and rounded growth zones clearly visible in synthetic Czochralski alexandrite. Bright field, shading, 45x. 18. One of the most unusual inclusions known in synthetic Czochralski alexandrites is hexagonal flat crystals of iridium, the form of such inclusions is called “bunker”. High “fence” around the perimeter and “entrance to the bunker” in the center. Fiber optic backlight, 80s. Alexandrite is a royal stone, the rarest of the first five precious stones. It is difficult to find a natural gem in jewelry stores. It is impossible to find an alexandrite larger than 3 carats. But even small specimens are too rare and too valuable. How to distinguish a natural nugget from a fake? This wonderful mineral was discovered in Russia in the 19th century while studying the Ural emerald mines. Finnish researcher N. Nordenskiöld, among other samples, discovered a strange-looking stone, which he initially mistook for a low-quality emerald. Imagine his surprise when it turned out that the mineral’s properties were very different from emerald.

Alexandrite properties

The mineral, which the discoverer took for an emerald, was superior to it in hardness. The new sample had a fairly high value – 8,5 on the Mohs scale instead of 7,5, typical for emerald. And the results of later studies turned out to be completely incredible: under artificial light, in the scientist’s hands there was not a green, but a bright red crystal. The discovery of the amazing properties of alexandrite happened just on the birthday of the future Russian emperor, and therefore it was named in honor of Alexander II, who was 16 years old at that time. So, the alexandrite stone is primarily known for its pleochroism, that is, the ability to change its color. This stone has three colors at once: green, dark red, yellow-orange, which change depending on the lighting. It is often said about it that alexandrite is a ruby ​​in the evening, and an emerald during the day. The color of the stone during the time of Alexander II symbolized the colors of luxury, and therefore it immediately received its rightful place in the hearts of the Russian aristocracy. Another factor that contributed to the gem’s popularity among the elite was that it was named after the emperor. Today the mineral has been studied, described long ago and is well known to collectors, but its natural samples are still not very accessible. The mineral is a rare variety of chrysoberyl, has a high density of 3,5-3,84 g, has a conchoidal fracture, and can be transparent or translucent. The main characteristics and formula of alexandrite can be found in the table:

Formula Al2BeO4
Daylight color dark blue-green, bluish green, dark grass green, olive green
Color under artificial light pink-raspberry, red-violet, purple
Hardness 8,5
Density 3,5–3,84 g/cm³
Transparency Transparent, translucent
Cleavage Imperfect
Kink Crustaceous

The composition and characteristics of this amazing gem endow it with unique optical properties for which we value this stone so much. In addition, alexandrite has useful magical properties – as esotericists say, it can change life for the better, achieve success and find peace of mind. It is often used during meditation to relax and gain positive energy. Sometimes they say that the stone brings sadness, but we will debunk this myth a little later.

Where is alexandrite mined?

The largest place for mining alexandrites is considered to be the Russian deposit, which is located in the Urals, in the village of Malysheva. Stones have been mined here since the 19th century. There are no analogues in the world in terms of the quality of samples and production volume, and in Russia this is the only deposit of alexandrites. Sri Lanka could be considered a competitor, but the chrysoberyls mined here do not have the alexandrite effect. In addition, due to residual iron impurities, most stones from Sri Lanka have a brown tint that flashes red in certain lighting. In addition, the volume of alexandrite production in this region is seriously declining from year to year. There are deposits in Zimbabwe and Madagascar, but alexandrites are rarely found there – sometimes isolated samples emerge, but nothing more. Therefore, the development of these mines is not taken seriously. Tanzania and Brazil could boast of interesting samples, but deliveries from there are now either not carried out, or interest in local stones has been lost. Prices for Brazilian alexandrites are extremely inflated, and their quality leaves much to be desired. Tanzanian gems have almost completely disappeared from the gem market. Taking into account the not-so-great popularity of Brazilian and African gems, Russian samples still remain leaders in the jewelry business.

What does alexandrite look like and what color does it come in?

The gem has high transparency and in natural daylight has a green color. Depending on the place of extraction and quality, it can have a light, olive or bluish undertone, and in some samples it has a rich, emerald green hue. If you change the lighting, alexandrite, like a chameleon, will give out a completely opposite color. In the evening, under the light of the lamps, the amazing gem flashes in shades of red – from pale pink to ruby. Some specimens surprise with another optical property – the “cat’s eye” effect. Taking a closer look, you can see a thin strip of light in them, which in shape really resembles the pupil of a cat’s eye. Such alexandrites are often found in Ceylon samples.

Why does alexandrite change color?

The unique ability of this stone to dramatically change color is associated with chromophore chromium ions in the composition, which reflect different spectra of light waves. That is, in daylight, the stone catches and reflects waves from the green and blue parts of the spectrum. And in artificial light, when the predominance of red rays is higher, alexandrite reflects precisely them. True, this does not mean that the color change is one hundred percent – the stone still balances between two states, therefore, after the transition, it retains the shade of the original or new color.

Precious or semi-precious?

Alexandrites are included in the list of precious stones according to the federal law “On Precious Metals and Precious Stones”. The law includes a list of seven gems, including diamonds, emeralds, rubies, sapphires and alexandrites. The remaining two items are pearls and amber. Classification by E.Ya. Kievlenko. which most experts focus on nowadays, also classifies alexandrite as a jewelry (precious) stone of the second order. In the table, the mineral is on a par with orange, purple and green sapphire, noble black opal and noble jadeite.

How to distinguish natural alexandrite from artificial

A natural transparent stone with a rich color of more than 3 carats is a collector’s item that can only be found at auctions. If you come across this option in a store, this is a fake. But imitations of alexandrite are different, and the words “artificial” and “fake” are not synonymous at all. Let’s explain now. Instead of alexandrite, natural stones are often found in jewelry: spinel, ruby, tourmaline, andalusite, although andalusite is too rare and is not used often. Ruby is also most often not inferior in price to the hero of our article. If tourmaline is passed off as alexandrite, the latter will change color depending on the viewing angle, and not on the lighting. Of the natural inserts, jewelers most often use spinel. She:

  • In daylight it does not have a yellow tint.
  • In sunlight it does not give any green tints.
  • This stone is several times cheaper.

Minerals have long been learned to grow under artificial conditions. In the Soviet Union, artificial alexandrites began to be synthesized in 1973, and they are of standard quality.

In the USA, our crystals are sold as natural stones from Brazil, Ceylon and Africa.

In Soviet jewelry, almost all inserts passed off as alexandrite are synthesized corundum. Real gems were mined in tiny quantities, and such luxury did not reach mere mortals.

Artificial stone can be distinguished from natural stone by the following characteristics:

  • Synthetic crystals are often large in size (more than 3 carats).
  • Artificial analogs have inclusions in the form of spheres. Natural stones have drop-shaped bubbles.
  • Synthetic crystals are usually brighter and more transparent than natural samples.

We will not talk in detail about cheap glass, since it is easily scratched and does not have any of the signs of natural stone.

The easiest way to determine the origin of a stone is to look at its certificate of authenticity, which the seller must provide. If this jewelry with alexandrite was found in your grandmother’s box, you can order an examination in a specialized gemological laboratory.

A true chameleon gem is incredibly expensive, and there are very few worthy examples, so even the most famous jewelry houses rarely spoil us with jewelry containing alexandrite. Neither private collectors nor businessmen who make money from fashion like to part with the precious mineral.

Purchasing a product with alexandrite of natural origin is real luck and an excellent investment. But finding a genuine mineral is a difficult task. One good thing is that science has reached such heights that modern grown analogues are sometimes difficult to distinguish from natural nuggets.

The physicochemical and aesthetic properties of such stones are identical to natural ones. In addition, the synthesized mineral does not have a “widow’s stone” trail; it suits most zodiac signs and will become the crown of jewelry in every jewelry box.

Which zodiac sign is suitable for alexandrite?

This magical stone of emperors can bring good luck, give inspiration and become a powerful amulet. But it is not suitable for all zodiac signs.

For example, astrologers are categorically against Virgos and Cancers wearing jewelry with this gem. Alexandrite is considered an energetically strong stone that can worsen life, bring misfortune or threaten representatives of these signs with danger. However, for any signs there is one exception: a strong attraction to a specific mineral is quite a sufficient reason to become its owner.

If Virgo or Cancer still really wants to add magical alexandrite to their collection and wear it at least occasionally, they can neutralize the negative impact with the help of helping talismans. For Virgo – pearls, citrine, garnet and topaz, and for Cancer – opal, tourmaline, sapphire and ruby. These stones suppress the energy of alexandrite, turning it into a beautiful piece of jewelry without much impact.

Perhaps this gem has the best compatibility with Aries, Gemini and Scorpio. These signs will feel the strong influence of their talisman, especially the ambitious Aries who love to get their way.

Controversial Geminis will feel the impact of the stone more strongly than other signs. They will be able to finally find mental balance and calm their fussy nature, and anxiety, which greatly interferes with the life of this sign, will also decrease. Focus, peace and self-confidence will become the bridge that will help you achieve great success.

Strong-willed Scorpios are often hindered by their excessive emotionality, especially in business relationships. An explosive character can completely destroy what has already been built, but the powerful alexandrite will not allow strong emotional outbursts.

Astrologers focus on one important feature: this stone is considered the patron of only that person who is ready to make every effort to overcome difficulties. At the same time, in moments of despair, the changeable mineral is ready to share its power and help find a worthy solution to the problem.

Alexandrite is good for Sagittarius, Aquarius and Pisces. Energetic Sagittarius becomes healthier and more purposeful under the influence of the gem. True, if you have a talisman decoration with you, you should not indulge in adventures; here the stone can fail.

Aquarians will gain clarity of thought by making alexandrite their amulet. Possessing strong empathy and the ability to look into the future, Aquarians will be able to develop these talents to the maximum.

Pisces will become luckier and feel the power of their intuition.

For other signs, the gem is unlikely to become a serious helper. Its influence on Leo, Libra and Capricorn is very insignificant, but creative people can still find it useful. For example, during a period of creative decline or melancholy, a wonderful pebble can lift your spirits and find a fresh look at a problem.

For convenience, we have made a zodiac compatibility table that will help you understand whether alexandrite is suitable for a specific sign:

“+++” – perfect compatibility;
“+” – can be worn;
“-” – incompatible

Finally, let’s dispel the dark myth that haunts our hero. The fact is that this stone is considered a “widow’s stone,” but there are no horrors or mysteries here. It’s just that alexandrite became especially popular in our country after the Great Patriotic War, that is, at a time when many men never returned from the front. It was then that the belief arose that the “widow’s” stone brings misfortune or the death of a loved one.

How to care for a stone

Caring for jewelry with alexandrite is not difficult, and if you regularly take care of your pets, then serious measures will not be needed. To make the stone look good. need to:

  • each time after removing accessories, carefully wipe them with microfiber or flannel;
  • store in a separate box to avoid scratching the stones;
  • avoid contact with household chemicals and cosmetics;
  • remove jewelry before playing sports, sauna or visiting the beach.

If a product with alexandrite still requires care, use a weak soap solution and a very soft brush:

  • dip the jewelry in a solution of soap and warm water;
  • Gently scrub the stone and the fastener that holds the stone with a soft brush;
  • rinse with clean running water;
  • let dry naturally
  • buff lightly with microfiber or other soft cloth.

Another option for those who are used to entrusting the care of things to real experts is to give the jewelry to a jeweler or take it to one of the salons of the OUR GOLD network for ultrasonic cleaning.

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