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The Rare Gem Series: Alexandrite

Once upon a time in Russia… Some dudes found a rock and named it after the crown prince since it was his birthday.

The end.

No wait, I mean: The Beginning.

A 1.29ct Russian Alexandrite, Tino Hammid Photography, Inc
A 1.29 carat Russian Alexandrite.

One day in the Summer of 1830 Finnish mineralogist Nils Gustaf Nordenskiöld (1792–1866) was sitting in his office at the Mining Board in Helsingfors when he received a parcel to examine.  Nils was pretty much the most renowned mineralogist of his day so shiny hunks of dirt got sent to him all the time.  No biggie.

Upon opening the contents of the parcel Nils said, “Green, transparent, shiny… Emerald” (or more accurately: “vihreä, tranparant, kiiltävä … smaragdi“), and almost didn’t conduct any further tests; but something just wasn’t sitting right with him.  He began to poke, scratch, smash, and do all the things a good mineralogist does with Earthly byproducts, and he couldn’t get over the fact that the stone was just too hard and not brittle enough to be an emerald.  Weird.

After fussing with it for a while Nils lost the sunlight so he grabbed some dinner and pondered this strange stone while he pushed peas around his plate.  Being a good scientist he abandoned his meal and returned to the lab to inspect the stone under candlelight.  “Mitä vittua?!” Nils half exclaimed/half asked.  The stone, which a few hours earlier had been deep green, was now a rich red!  The next morning the stone was no longer red and had returned to its former deep green!  “Voi Luoja!”

This was no emerald.

The package with the strange stone had come from Count Lev Aleksevich von Perovski (1792-1856) who at the time was trying to climb the social ladder as the royal mineralogist for Tsar Nicholas I of Russia.  Perovski had also identified the stone as an emerald, but the problem was that he kind of sucked at his job, so he sent a specimen to Nils to double check his “work”.

Earlier that Summer Perovski’s team had been poking around in the Izumrudnye Kopi (Emerald mines) in the Ural Mountains (you remember the Urals, that is where Demantoid Garnets were discovered as told via the previous Rare Gem Series post: http://noospheregeologic.com/blog/2012/10/11/the-rare-gem-series-demantoid-garnet/) when they discovered the stones in an alluvial deposit (think gravel river bed) along the Tokovaya River.  By 1831 Perovski had opened his new “emerald” mine and was in full whipping peasants mode to dig faster when Nils sent him a message:

“This ain’t no emerald, genius.  It’s a color-change chrysoberyl and I am calling it  ‘diaphanite‘ which is Greek for ‘something your small brain cannot comprehend’.”

I paraphrase, of course.

Perovski, ever the ladder climber, had other plans in mind.  He wanted to ingratiate himself further with the royal family, Perovski spun a tale that he had discovered it April 17, 1834, the sixteenth birthday of the crown prince and heir to the throne Alexander II, and named it “Alexandrite” in his honor.

Perovski didn’t know how to be a very good scientist, but he knew how to play the game like a champ.  His ploy was well received and he got his ass ingratiated into the royal family like no body’s business; creating the Russian Geographical Society in 1845 and being named the Minister of Internal Affairs, and later the Vice President of the Appanage Department by Tsar Nicholas I (basically, he became the dude in charge of the imperial family’s estates, investments, personal property, and income).  This fancy post also meant that Perovski was in charge of the jeweled trinkets and souvenirs the imperial lapists and jewelers created as rewards for the Tsar’s subjects.

Perovski was a greedy piece of crap.  He used his position of power to threaten, bribe and steal the best stones for the Appanage collection which often found their ways into his own personal collection.  One of Perovski’s underlings, Yakov Kokovin, the director of the Ekaterinburg lapidary, stole an amazing Ural emerald and was caught by Perovski and was braought to trail and later was “compelled” to commit suicide in the dreadful Ekaterinburg Prison.  When Perovski finally kicked the bucket in 1856, the stone, which had now become known as the “Kokovin Emerald”, was found in Perovski’s personal collection. Dick.

Alexandrite quickly became one of the most desirable gem stones in the world. Many sources I have read claim that this is because red and green were the primary colors on the Russian Imperial Flag.  Well, considering that the Imperial Flag was red white and blue, this “fact” is bullshit.  It became popular because it is a rad stone that CHANGES FREAKING COLOR!  Imagine yourself a rich asshole living in Feudal Europe:  you have a fancy house, you have some books, you have a really comfy chair, you have candelabras, you have… well, that is pretty much it.  Some other rich asshole comes along and shows you his new ring that is green during the day and red at night.  “Holy shit!” You’d yell out, “I’ve got to get me one of those, especially since the invention of television won’t happen for another 90 years!”

A beautiful example of a natural Alexandrite in matrix
A beautiful example of a natural Alexandrite in matrix, from Kevin Ward at Exceptional Minerals

By the beginning of the 20th century Russia had pretty much gobbled up all of the Alexandrites in the Urals.  There has been no significant deposits of Alexandrite discovered in Mother Russia since the 1917 revolution.  To this day the best red/green specimens are Russian stones.  They are also the most valuable.

As mentioned above, Alexandrites are a form of chrysoberyl.  While chrysoberyls contain beryllium, they are not related to beryls (emeralds, aquamarine, Bixbite, Morganite, etc…)…  Only sort of-ish, I guess.  Here’s how I would describe the stone as if I were the beaten, over-qualified interpretive guide of the hypothetical “Chrysoberyl Museum” leading a group of tourists in flip flops and aloha shirts:

Leading the tour group into the great hall of the museum: “Chrysoberyls are different from beryls mainly because of their crystal structure.  Beryls are silicates that have big molecules and chrysoberyls only have one beryllium atom so there is less crap glommed onto the beryl atom.  Chrysoberyls only form in pegmatites–“

“But so do Beryls!” Says some interrupting know it all eight year old.

“Shut up, not all of them do!” Says the pissed off tour guide, “Some beryls form in rhyolites. Ha! Now shut your yap and let me do my damned job!”

“What’s a pegmatite?” Asks some oafish dad dragging his bored children along (noses buried in their cell phones).

“Well, that’s a stupid question,” replies the guide (the know it all eight year old nods his head in agreement), “Especially considering that there isn’t a geologist alive that can accurately describe it to you without sounding like a child explaining the story line to “Syriana”.  The facts: a pegmatite is an igneous rock (meaning that it was once molten magma goo that formed far beneath the crust); it created big crystals in its matrix as it cooled; the stuff inside those crystals is similar to that of granite (you know, the kitchen counters in the homes of yuppies); and for geologists it’s like porn, you know it when you see it.  Does that help?”


“Whatever.  Moving on.  When this magma comes oozing up deep from the mantle, it can begin to gather up a bunch of ground water as it moves higher through the Earth’s crust.  The magma is too hot to allow the now super-heated water to join into the formation of any crystals inside the magma.  By the time the magma had mostly cooled, the trapped water formed chrysoberyl in the cracks and crevices out of bits of beryllium and aluminum.  Basically, if it wasn’t for the water being present in the magma, the oxide that is chrysoberyl could not find the oxygen needed to form in the first place!  All you need to make Alexandrite from here is some chromium and your set!  Pretty bitchin’, right?  Does that help?”


The eight year old nods because he already knew that.

*Sigh* “OK, beryls are a silicates that have the basic chemical composition of Be3Al2(SiO3)6, meaning the crystalline molecule forms an asymmetrical spur on one side of the molecule leading to a hexagonal crystal when the molecules are stacked, like parallelograms.  While chrysoberyls are tinier than beryls and only have one beryllium atom to form around, so their crystal structure is much more symmetrical and forms an orthorhombic arrangements, sort of like cubes with dips in the middle.  Does that help?”


Eight year old roles his eyes because everyone should know that by now.

Considering that none of you have learned anything from the prolonged inside joke above, I digress…  To find Chrysoberyls one essentially needs to find pegmatites with beryllium and that also look like they had a lot of water in them when they formed.  To find Alexandrites you find those same pegmatites but also look for evidence of there being chromium too.

The great things about gemstones is that there is always a new discovery to be found somewhere.  Once the Ural source for these groovy stones played out, other deposits began to be discovered.  Also, these pegmatites don’t just form chrysoberyls, they will have also have formed fantastic crystals of quartz, garnets, tourmaline, spinel, and corundum to boot.  So, where there are chrysoberyls there are a shit load of other stuff to make some overlord really rich.

Most significant mineral discoveries come from alluvial deposits along some river or stream.  In early 20th century discoveries of Alexandrite were made in Sri Lanka and India where the stones were nothing more than weathered pebbles found in streams.  The stones are not of the most vivid color; with color changes going from brownish-orange to yellowish-brown.  Other discoveries of Alexandrites have been made in Tanzania, Myanmar, Zimbabwe, and Brazil with most of the today’s production coming from mines in India and Brazil.

In Brazil, Alexandrites and other forms of chrysoberyls are found in the states of Espento Santos, Bahia, and Minas Gerais.  Minas Gerais means “general mines” and was settled by prospectors looking for gold.  Later, discoveries of diamonds, rhodonite, tourmalines, garnets, and everything else one would expect made it one of the great gem centers of the world.  Miners in Minas Gerais work at the earth in the most primitive fashion imaginable.  Modern mining technology isn’t really needed in an area where one can unearth a million dollar stone while digging a latrine, or putting a fence post in the ground!  Noosphere Geologic has a near flawless 8.53 carat oval cut Brazilian Alexandrite as the flagship stone in our collection.

An 8.53ct oval cut Brazilian Alexandrite that is part of the Noosphere Geologic Collection
An 8.53ct oval cut Brazilian Alexandrite that is part of the Noosphere Geologic Collection

There have been several places in North America where one can find chrysoberyls: Pend Orielle County, Washington (also home to some GIGANTIC green beryls); the Black Hills of South Dakota; the border region of Nevada and Arizona in Northwestern Arizona; in North Central Colorado in the Front Range; and all along the Appalachian Mountains (basically the same age and type of mountains as the Urals) from North Carolina, Virginia, and all throughout New England.  The only place so far, that I know of, where Alexandrites have been found in the United States is at the La Madera Mountain mine in Rio Arriba County, in central New Mexico, which is reported to produce occasional small chrysoberyl crystals with weak color change.  I have yet to see any of these stones first hand, but I plan on getting me some!

Natural Alexandrites are among the most valuable stones in the world. True, clean red/green stones sell for more than $10,000 per carat.  When the stones have more of a brownish or orange tint to the colors they sell for about $2,000 per carat; with raspberry/blue stones (common to the Brazilian variety) selling for about$8,000-$10,000 per carat.  If the stone is Russian then expect to pay $50,000 per carat.  If the stone is Russian, with red/green color change, is over ten carats, and is inclusion-free, just put a million dollar minimum on it from the get-go.

You can find a bunch of beautiful examples of lab-created synthetic Alexandrites out there, as well as imitation stones that are usually lab-created colorchange spinel or colorchange sapphire that are made with vanadium.  Sometimes you can find “crown” or “doublet” Alexandrites that have thin, real sheets of Alexandrite glued to a different stone and sold as the real thing.  If you are going to purchase an Alexandrite, take it to someone who knows what they are doing.  Look for bubbles or curved striations inside of the stone with a microscope; this is a sign that it is lab-created and should only sell for a few dollars per carat.  Also, having a certification from a reputable gemological laboratory is a good idea (like the GIA, EGL, AGL, Swiss Lab, IGTL, etc…), this will give you confidence that what you are purchasing is the real deal.  You don’t want to drop $40,000 on that engagement ring to find out that you just bought a $5 stone that was made at a lab in an office park in Bangkok!



The Rare Gem Series: Spinel (The Balas Ruby)

Spinel?  Really, that cheap fake crap that you can get at Forever 21? Rare?  You bet.  To explain why, I have to take you time travelling; going back maybe a thousand years to the domains of some lost civilizations in Central Asia and the Middle East.

Spinel used to not exist; way back when, there were only rubies and sapphires. If it was red, it was a ruby.  If it was a color other than red it was a sapphire.  That was a pretty simple classification, the type of classification that drives my birding roommate up the wall.  To me there are six kinds of birds:  crows, seagulls, not-crows, and not-seagulls, chickens, not-chickens.  I know I’m wrong, but it’s too much fun to watch him pop a vessel when I play the moron.

In the mountains of what is now the border region between Afghanistan and Tajikistan shiny, gemmy red stones were discovered and a very primitive mining began.

The Black Prince Ruby
Queen Elizabeth the Second’s crown is adorned with the Black Prince Ruby, that is actually a spinel.

Who commissioned the mine? When were they opened?  The first known historical reference to these “rubies” was by the Central Asian Divinci of his day, Abū al-Rayhān Muhammad ibn Ahmad al-Bīrūnī (973-1048):

Ruby mines are situated near the village of Warzqanj which is situated in the direction of Kharukhan while going from Badakhshan at three days’ journey. It is a part of an emperor’s domain, the capital of which is Shakasim, which is close to the mines producing this stone. The approach to the mines via this route is easier, and it passes between Shakkasmi and Shaknan. This is why the governor of Wakhan keeps the most precious jewels for himself, and precious jewels pass this way clandestinely. Jewels weighing beyond a certain size are prohibited from being carried outside the mine, and only stones weighing up to the sizes he has fixed or specified are permitted to be taken out.

It is said that the mine was located when there was an earthquake in the area and the mountain was cloven. Big rocks fell down and everything was destroyed. Rubies were disgorged in the process. Women thought the stone was something with which clothes could be dyed. They ground the stones, but no colour came out. Women showed the rubies to men and the matter was publicised. The king ordered the miners to locate the mine. When they found it they began to excavate it.

al-Bīrūnī 11th Century

al-Bīrūnī was an amazing person, by the way.  A true polymath (renaissance man, genius, righteous dude), al-Bīrūnī spoke Persian, Hebrew, Sanskrit, Greek, Aramaic, Arabic, Syriac, and probably others.  He was a master of physics, astronomy, mathematics, linguistics, is known as the “the world’s first anthropologist”, and the founder of geodesy (the science of accurately measuring the surface, shape, and features of the Earth).  This article isn’t about al-Bīrūnī, but maybe a future one will be, until then read up on the dude, he was amazing.

 Abū al-Rayhān Muhammad ibn Ahmad al-Bīrūnī
The Divinci of his day… I guess Divinci should be called the Biruni of his day since he came afterwards.

I digress… In the early 1970s, Dr. Mira Alekseyevna Bubnova,  an anthropologist from the Tajik Academy of Sciences, found evidence that mining operations may have began as early as the 7th century.  The empire of Shakasim funded and controlled the mining operations for the “rubies” and the local governor of Wakhan managed to keep the best stones for himself.  There were also problems of miners “high-grading”  the nicer stones for themselves (“high-grading”: that act of sneaking big, fancy stones or gold nuggets, etc, out of a mine) and then smuggling them out of the realm.  The laws were fairly strict, only a stone smaller than a certain size was allowed to be removed from the mines, leaving many of the greatest stones right where they were found.

Some of the most famous rubies in the world came from these mines; the Timur Ruby, the Samarian Spinel, and the Black Prince Ruby.  Wars were fought over various crown jewels; the majority of which managed to be coalesced by the Mughal Empire.  The Mughals were a mix of Persian and Mongolian ancestry that were direct descendants of the Genghis Khan.  These warrior lords invaded and ruled much of the Indian subcontinent from the 16th to the 19th centuries.  The wealth of the maharajahs who ruled the empire were legendary.  Portuguese and English sailors who were presented to the courts of these men told the world of the piles of jewels that surrounded them in the throne rooms and of the elaborate, ornate jewelry that adorned the monarchs and their family.  Much of the gold that was discovered in the gold rushes of the Yukon, California, and Colorado went to the maharajahs to create their jewelry; where they traded their lesser stones for the gold.  One particular tradition that began with the Mughal Maharajahs was to inscribe their names on the grand stones.  Some saw this as vandalism while others, like Emperor Jehangir, saw it as a way for their name to live on forever.  In his case, it has.

Rubies and Sapphires were so important to the world’s powers that England overthrew Burma to take theirs.  It was not until gemological sciences started to become more refined by the 19th century, as did all sciences with the Industrial Revolution, that was realized that what we had been calling rubies and sapphires were not really exactly what we thought they were, but different stones that were basically named wrong.  It turns out that there were two stones involved, just not he distinction of rubies and sapphires like everyone thought, but of corundum and spinel.

The problem: Scientists had to decide on their definitions.  Which stone would remain a “ruby”, which stone would remain a “sapphire”, and which stone would get the new moniker of “spinel”.  Well, 150 years later we have our answer.  If it was corundum and red, it was called a “ruby”.  If it was corundum and any other color, science henceforth dubbed thee “sapphire”.  Everything else then became “spinel”.  The downside to this was that the largest red stones in the crown jewels of Iran, Russia, England, France, and India were all ignored as useless because they were no longer “rubies” as previously thought.  Spinel’s problem was that rubies had 4,000 years of marketing behind them, and spinel had none.  If the scientists had decided the other way around and called what are now known as rubies and sapphires “spinels” instead things would have turned out different indeed.

Only recently (in the last decade or so), have spinels started to get noticed in their own right. Jewelers and collectors started seeing the inherent beauty in the wide array of colors of spinels.  Those in the know have also realized how rare these stones actually are.  Historically, gem-quality spinel was only found in three places around the world: Badakshan (Afghanistan/Tajikistan); the gravels of Sri Lanka; and Mogok (Burma/Myanmar).  Two recent discoveries in Luc Yen, Vietnam and in Mahenge, Tanzania have come to the forefront as of late.  Mahenge is the real reason for spinel’s revival.  The discovery of the neon orange/red/pink stones there have driven up prices world-wide with stones larger than 5 carats fetching $10,000 to $20,000 per carat, now rivaling the finest rubies of the same quality and size.

Spinels are usually found in metamorphic rock, marble mostly, all over the world.  There are deposits on every continent, including North America.  It is the discovery of gem-quality stones that evade us here in the “New World”.  You can find examples of ugly, brown cubic crystals of spinel in New York and New Jersey, and Ontario.  There are reports of gem-quality stones in East Fresno County, CA of various colors and sizes–I haven’t seen any yet, nor can I find any photographs of these supposed spinels.

I listed a couple famous spinels from the mines of Central Asia a little earlier.  The current world record holder is the Samarian Spinel at 500cts.  The stone is heavily included, brownish red in color, “polished in the rough”, and worth tens of millions of dollars.  In ancient times spinels, and most stones in general, were polished in their rough form as exact faceting methods where not necessarily invented yet.  In the 18th century, the Persian King Nader Shah captured the stone and its 270ct cousin in an invasion and conquest of India.  There is a hole drilled in the Samarian that was supposedly used to affix it

Pink Mahenge Spinels
Spinels from Tanzania that are famous for their neon characteristics. From Swala gem Traders

around the neck of the Biblical Golden Calf that the Israelites created while Moses was receiving the Ten Commandments.  The problem is that the Samarian was most likely from the mines of Northern Afghanistan and was mined a couple thousand years after Moses yelled at the idol worshipers in Sinai.

The most valuable spinels are as follows: Balas rubies (the stones that were originally thought to be rubies from Afghanistan/Tajikistan); neon Mehenge spinels (a 10ct stone will cost you about $200k!); pigeon blood spinels, usually from Mogok, Sri Lanka, or Vietnam; and cobalt spinels (often from Sri Lanka or Tanzania, they are a steely blue hue and color come from, you guessed it, cobalt!) which can be valued upwards of $5,000 per carat.

Cobalt Spinels
Tanzanian Cobalt Spinels from Pala Gems

This brings us to my big announcement:

I proudly present the new record holding polished spinel:  I am the proud owner of the The Sinful Red Spinel (named such because it is sinfully ugly).  The original stone was 2000cts and was found embedded in white marble in Mahenge, Tanzania.  I received the stone in the rough and polished it myself.  Keeping with the tradition of the great Mughal emperors the Sinful Red is polished in the rough and weighs in at a hefty 689cts crushing the old world record holder!

I have a large collection of Tanzanian and Vietnamese spinels that I will be polishing in the coming months and I look forward to sharing them with you.

10.24ct Ceylon raspberry spinel from Sri Lanka
10.24ct Ceylon raspberry spinel from Sri Lanka. Owned by Noosphere Geologic.

7ct Mogok spinel.
7ct Mogok, Burma spinel. Extremely rare, owned by Noosphere Geologic.