Thursday, May 21, 2020

http://earthsci.org/mineral/mindep/gem_dep/gem_dep.html

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Alexandrite was first discovered in Russia in the early 1800's. It was named in honor of Alexandar Nicholavich, who was later to become the Russian Czar Alexander II. Legend has it that the gemstone was discovered on the future Czar's birthday and named in his honor, though the factual nature of this is disputed.

The unique color change habit of Alexandrite is caused by slight impurities of the element chromium. The most desirable colors of Alexandrite are those that show a clearly visible pure hue color change, such as a pure green/blue in daylight to a pure red in incandescent light.

In addition to its color-changing habit, Alexandrite is a pleochroic gem, showing different color intensity when viewed at different angles. This factor must be taken into account when cutting Alexandrite gemstones. Alexandrite exhibiting chatoyancy does exist but is very rare, thus Alexandrite Cat's eye is rarely available.

Most the time, natural stones are identified by having some inclusions. Even if they are microscopic. Most stones are considered VSS if they have no inclusions under 10X magnification. Try using 100X to look for inclusions if the stone is clean at 10X. This isn't a sure thing. They have begun making lab created stones with inclusions to appear like they are the real thing. I have seen more and more glass "stones" on ebay lately. They sell them as topaz, beryl, ect. when actually it is colored glass cut into a stone. Glass has a hardness of 5.5 - 6.5. These people get away with this because most people do not want to scratch their stones. Some things that will scratch glass are a sharp piece of amethyst or schorl. Since the stone you bought was labeled emerald, I'd first check it for inclusions under a high powered lens. If you see no inclusions, my guess would be lab created. I doubt they would be selling glass, but you can also try the scratch test with a piece of amethyst. If it scratches, it is not beryl at all. Amethyst cannot scratch beryl (emerald).

Average retail prices for alexandrite 2007 - 2008
Faceted (Alexandrite)	0.5 to 1 carat	1 carat plus
Top Red/Green	$5,000 to $15,000/ct	to $100,000/ct
Medium Red/Green	$3,000 to $9,000/ct	to 60,000/ct
Slight Red/Green	$100 to $2,500/ct	to $6,000/ct
Other colors	$1,100 to $8,000/ct	to $10,000/ct
Cabochon ( Alexandrite)	0.5 to 1 carat	1 carat plus
Strong red/green	$500 to $2,500/ct	to $30,000/ct
Cabochon (Cat´s Eye)	0.5 to 1 carat	1 carat plus
Strong red/green	$1,500 to $5,000	N/A

Alexandrite commands a high price equivalent to or even exceeding the price of gemstones like, sapphires, rubies, emeralds, and diamonds. Alexandrite from Russia would be more valuable if their origin could be verified and if they were of superior quality. Top-quality alexandrite from Russia has sold for as much as $3000 to $10,000 for a one-carat gem. The price of alexandrite has risen in recent years due to high international demand, especially from Japan, but as a gemstone investment, alexandrite is a good choice because of its rarity, durability and distinctive historical significance.

Here is the classic definition of Alexandrite’s color change ranges:

Daylight (sunlight)	Incandescent light
blue Green	orange Red
very slightly blue Green	Red
Green	slightly purple Red
slightly Green	Purple Red
yellow Green	Red purple or Purple red

There are a couple of factors that make an Alexandrite an Alexandrite. It must change to one of the colors or color combinations that I stated earler in both Sunlight and Candlelight. It must have a color change percentage that is over 30% or it will be considered a color change Chrysoberyl.

There are many other factors on which an Alexandrite is judged. Besides the famous 4 C's of which all gemstones are graded (Color, Cut, Clarity and Carat.) An Alexandrite unlike them, will be judged on the strength of it's color change, and the amount of saturation (how light or dark the color saturation is.) Many folks are dissapointed when an Alexandrite has flaws or inclusions. I will tell you that any Alexandrite over 2 carats that is flawless is rarer than Alexandrite itself, and you should be careful to buy such an Alexandrite without these notable Inclusions. Inclusions show that the Alexandrite is in fact Natural or is certainly more pron to be a Natural gemstone. Nothing is conclusive without testing. While inclusions are not pretty in most cases, it is in fact the color change of an Alexandrite that is the most important thing, PERIOD!! In other words, a one Carat flawless Alexandrite with little to no color change is worth much much less than a 1 Carat flawed Alexandrite with very STRONG color change.

There are many informative websites on the internet that can help explain what Alexandrite is and what it is not. Type in your browser..."False Marketing of Alexandrite", and you will find an article, that explains what colors an Alexandrite must change to, to be considered an Alexandrite. Please be sure to know your seller if buying an Alexandrite without a C.O.A, and if they offer a Certificate of Authenticity from a reputable Gem lab such as AIGS, GIA or AGS so much the better. These labs are meant to help identify the gemstone as being what they say it is. If the lab has determined that the Gemstone is an Alexandrite for example, then it is an Alexandrite! They do several tests such as UV, Specific Gravity tests, use of a Refractometer etc. to determine the authenticity of the Gemstone. Natural Chrysoberyl that is marked on the C.O.A as being Alexandrite or Natural Chrysoberyl-Alexandrite, is indeed an Alexandrite.

Thank you and good luck in all of your Alexandrite purchases....

Average retail prices for alexandrite 2007 - 2008
Faceted (Alexandrite)	0.5 to 1 carat	1 carat plus
Top Red/Green	$5,000 to $15,000/ct	to $100,000/ct
Medium Red/Green	$3,000 to $9,000/ct	to 60,000/ct
Slight Red/Green	$100 to $2,500/ct	to $6,000/ct
Other colors	$1,100 to $8,000/ct	to $10,000/ct
Cabochon ( Alexandrite)	0.5 to 1 carat	1 carat plus
Strong red/green	$500 to $2,500/ct	to $30,000/ct
Cabochon (Cat´s Eye)	0.5 to 1 carat	1 carat plus
Strong red/green	$1,500 to $5,000	N/A

The Color of an Alexandrite Gemstone Fascinates A Woman

Alexandrite, the name itself reminds us of the name of a great warrior. The discovery of the stone has a strong history related with self. It derives its stipulate from the Russian Knave Czar Alexander II. It is said that the stone was discovered at the day of the king’s birth good terms the year 1834 and hence the name Alexandrite was kept. The stone was rather than excavated in the Ural Mountains of Russia. Initially, the stipulate in connection with the stone was kept insomuch as diaphanite, which implicated to appear in the Greek language simply before long the sobriquet was changed versus Alexandrite.

The speciality in reference to the stone is the frequent change in its color under another happy conditions. The stone exhibits green color at all events placed short of noontide light and red notwithstanding placed sub lamplight. This matter of fact is known as the alexandrite effect. The stone also displays a ilk of banneret alike whereas orange, red, yellow and emerald unseasoned when views from alternate angles. Hence, the goods is also named as pleochroic gem. The property of this stone to pageant unlike colors makes yourself one of the lordship rarely occurring gemstone in connection with this planet.

The green color relative to the stone is evenhanded to the presence of Chromium. This is the same element which is found in the emerald gemstone. The color therewith varies according to the country of origin. For instance: those that are stereotype in Sri Lanka have got Khaki coronet a tenne color, the ones not counting Zimbabwe are purple toward color. The Tanzanian Alexandrite on the other hand has lighter color. A Brazilian Alexandrite’s color varies discounting blue so purple.

Color plays a very important task while purchasing an Alexandrite Gemstone. Infact, it all depends as regards the way the stone is topical cut. The stones that are as per usual available way in the mart today can see a slight change in the color. The variation to the color may take state from yellowish green headed for orange also. The value of an alexandrite is more than an emerald, blue sapphire and ruby. Amongst all the countries, Sri Lanka is parol to invent the purest Alexandrites.

These stones are pawed-over clout a wide variety referring to jewellery. In the wrinkly times they were used in passage to artifice antique Russian as well as Fossil jewellery. Due against its purism and durability, the stone battlewagon be used in any form of jewellery like pendants, earrings. Most of them are forfeit passage making anniversary bands, halo designing jewellery as well as eternity bands. It is also used as a gift for celebrating the 55th lovemaking anniversary.

As far as cleaning of the stone is concerned, it is necessitous to clean them quite carefully. When cleaning the stone, a mild soap had better be unnew. The temperature of the water should solid be warm or at room temperature. It is accommodate to file away the stone as long as engaging in some form of instrumental music. Like this, taking a good care anent the stone will certainly increase its effects and you can also continue so as to wear the genuine article for a prolonged comma of shot.

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alexandrite gemstone name stone color name alexandrite green color alexandrite alexandrite effect exhibits green color color varies lighter color tanzanian alexandrite gemstone fascinates stone exhibits green brown color stone exhibits color plays alexandrite gemstone fascinates sri lanka used

Color Changing

The Coolest thing about Alexandrites is their Famous Color Changing Abilities. (Sometimes called the Alexandrite Effect) In different lighting Alexandrites will look like two totally different Gemstones. In Daylight or Fluorescent lighting the Stone can appear Green. Under Incandescent Light or Light Bulbs the Stone can appear Red, Purple or Brown.

What causes this Cool Color Change in Alexandrites? Alexandrites are a PleochroicStone (it can show more than one Color at a time)… Pleochroism and our eyes that is! Our eyes can perceive Alexandrite’s Different Wavelengths and show them off as Greens and Reds depending on the Different Lighting Situations. Hence we see the different Spectrums of Light and the Stone looks either Green or Red to us. (And you thought it was Magic!)

Is alexandrite the most expensive gemstone in the world?

Along with diamonds, rubies, and emeralds, top quality alexandrites are among the most expensive gemstones in the world. In larger sizes over 4.00 or 5.00cts., Burmese rubies are more rare and expensive than alexandrites but in sizes below 1.00cts., alexandrites are generally more expensive than both rubies and diamonds. It is rare to find alexandrites weighing over 0.25 carat and even tiny melee sizes with a good color change are very hard to find at any price. Stones weighing less than 0.50 carat can be worth several thousand dollars at retail prices and stones over one carat may retail for ten times more. Some top-quality one-carat gems from Russia were said to have been sold for as much $10,000. Fine alexandrites weighing more than 5.00cts. are extremely rare and may retail for as much as $40,000/ct.

A gemstone for experts and gemstone lovers

With its good hardness of 8.5, alexandrite is an uncomplicated stone to wear. The more distinct the change of colour, the more valuable the stone. A fine alexandrite should show a vivid bluish-green in daylight and a purplish-red in artificial light, without any trace of undesirable brown or grey. If the origin of the stone is known beyond dispute to be Russia, we are talking about a real rarity of enormous value. Finely faceted alexandrites above one carat are thus among the most expensive gemstones in the world, rarer than fine ruby, sapphire or emerald.

Alexandrite is a stone for experts, enthusiasts and connoisseurs, a true understatement stone. Its uniqueness and high value are not evident at first sight. The mysterious colour change will only occur on exposure to different light sources. But if you really get involved in alexandrite, you will be utterly fascinated by this gem. Maybe you will also feel some of the mysterious magic and lore ascribed to it. It is considered a stone of very good omen. In critical situations it is supposed to strengthen the wearer’s intuition, and thus help him or her find new ways forward in situations where logic will not provide an answer. Alexandrite is also reputed to aid creativity and inspire the imagination.

The vast majority of Alexandrite are under one carat. Upto one carat, the going price is said to be $15,000. Over one carat, the price varies from $ 50,000 to$70,000 per carat though price has reportedly not been fixed for an Alexandrite above 10 carats.

Alexandrite is an uncomplicated stone to wear. The more distinct the change of colour, the more valuable the stone. Finely faceted alexandrites above one carat are thus among the most expensive gemstones in the world, rarer than fine ruby, sapphire or emerald.

These wonderful stones exhibit the green to red shift characteristic of the dichroic Alexandrite; which is the trait which draws so much interest to them. It was explained to me that the percentage of change, whether it be 20% or 90% was one of the most important aspects of this precious gem, and that care should be taken when examining them under different lights. “White light will show off the green color, which should be a deep green with some browns or reddish tints. These other colors will help you determine how much ‘shift’ will occur when you look at the stone under yellow light or in sunlight. When away from white light, you want to look for bright flashes of red, and a nice overall reddish tint to the stone.”

As the conversation turned to valuing the stones, and insuring that the buyer or designer doesn’t overpay, some guidelines from Mr. Ahmed were very helpful. For ‘average’ stones, that is stones with a 20-35% shift in colors, weighing less than 3 carats, you should expect to pay between $3-500 per carat. Higher quality stones, those with say, 80-90% shift in color are much more dear, with 1 carat stones fetching about $3,500 a carat, 3-4 carat stones bringing $7,000 per carat, and nearly unheard of 10 carat and higher stones bringing $15,000 per carat or better due to their rarity.

Five Star Gems brings Alexandrite from India to Tucson Gem Show

On February 22nd, 2013 / About JOGS Gem and Jewelry Show, Exhibitor Profile, Gem & Jewelry News, Jewelry Products / 1 Comment

When you spend your professional life surrounded by beautiful gems and jewelry, it is all too easy to get a little jaded (sorry for the pun). What might draw ‘Ooohs’ and ‘Aaahs’ in any other circumstances, can begin to bring just a raised eyebrow, if even that. So, like the many thousands from around the world who flock to Tucson for the annual Tucson Gem &Mineral Show, I keep my eyes peeled for the unique or the extraordinary.

Luckily, this year I found a number of rare, unusual and exotic stones in tucked away corners of the show. One of the exhibitors in one of these corners this year is Ikram Ahmed from Five Star Gems who is exhibiting at the end of one of the grand halls of JOGS Gem & Jewelry show. What’s so special about this exhibitor’s offerings? Well, he has some excellent examples of a pretty rare stone sourced in an unexpected place—Alexandrite from India; and boy, is it nice!

I took a few minutes of Mr. Ahmed’s time, and asked him about his gems, and will share with you what I learned from him.

Found only in small pockets, veins and mines of Alexandrite being nearly unheard of, the beautiful gems Mr. Ahmed brings to Tucson are sourced by his buyers from small villages in rural India. Rarely measuring more than a few carats in size “Larger stones are too rare, no one finds large 10 carat Alexandrite of good quality.” Even though they have been known for about 400 years now, and deposits outside of Russia have been found in Brazil, and more recently in India, this is one of the rarer stones available on the market.

Clarity is another significant grading factor. As with most gems, the majority of what nature offers us is cabbing grade, not clean facetable material. However, with Alexandrite, the color change has more effect on value than clarity. For example, say you had two gems weighing a half-carat each. One gem is eye clean, with a 50% brownish/red to greenish/blue color change. The other, an opaque cab with a 100% green to red color change, would be higher in value.

Size is always a significant factor in value. The largest Alexandrite known is a yellow/green gem weighing 74.4 carats. The largest Russian gems are about 30 carats. However, the vast majority of Alexandrite are under one carat. You can see this reflected in our Price Guide. In sizes up to one carat, top quality natural gems sell for $15,000. Over one carat, the prices range from $50,000 to $70,000 per carat.

Distinguishing Between Natural and Synthetic Alexandrite

We receive many emails asking what an inherited gem is worth. Most people do not realize that there are many synthetic Alexandrite and simulants (look-alikes) on the market. Some of these have been available nearly as long as the natural gem.

While determining the exact origin of a gem is a matter for professionals, here is a brief guideline. If the gem has good clarity, strong color change, reasonable size, and your grandmother was not exceptionally wealthy, it is most likely a synthetic.

Also see “The Misconception and Erroneous Marketing of Alexandrite Vs Color C

Even at wholesale prices, there is still significant risk. For example Tanzanite that was around $500 per ct a few years ago is now $150 per ct. On the other hand, Tsavorite has increased from $250 per ct to perhaps as high as $1,000 per ct for larger sizes, in the same period.

Blue sapphires right now are at a comparatively low price. Even stones 5ct plus can be found at under $500 per ct (albeit with some treatment). Pink sapphires and rubies are at comparatively higher prices because of demand from China. While at the same time there are many very poor quality rubies, with intense heat and colour treatment, entering the market that seem quite cheap.

I believe there is good investment opportunity for Alexandrite, if you can find it. I was recently shown a beautiful 1.1ct stone with good red/green colour change at an asking price of $10,000, where the 'tourist' retail price was $35,000.

ALEXENDERGEMS GEMS

Thursday, May 21, 2020

3 comments:

ALEXANDRITE

Alexandrite - Benefits, Power and Energy

Color Changing

Is alexandrite the most expensive gemstone in the world?

Five Star Gems brings Alexandrite from India to Tucson Gem Show

Distinguishing Between Natural and Synthetic Alexandrite

THE A – Z OF COLOURED GEMSTONES

Example	Alexandrite	Natural Light - Candle Light
Carat Weight: 8.00ct.	Cut: Squarish Cushion
Size: 12.7x11.9mm	Color: brownish-Green (in fluo. light), changing to brownish-purple (in incand. light)
Clarity: VS, Type II near flawless to unaided eye	Origin: Sri-Lanka
Price per carat: $18,000.00	Enhancement code - N No evidence of heat or other enhancement

Example	Alexandrite	Natural Light - Candle Light
Carat Weight: 4.00ct.	Cut: Cushion
Size: 9.3x10.9mm	Color: Green (in fluo. light), changing to violetish-purple (in incand. light)
Clarity: VS, Type II near flawless to unaided eye	Origin: Ceylon (Ratnapura)
Price per carat: $20,000.00	Enhancement code - N No evidence of heat or other enhancement