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Wednesday, September 8, 2010

Alexandrite

Alexandrite, a member of the chrysoberyl family of gems is one of the most expensive gem materials on the market. Due to the way the stones absorb light, the color of these stones will change from a greenish blue color to a purplish red color depending on their light source (fluorescent/incandescent). As with all gem materials there is better and worse material out there so it is possible that lower grade material will not be so expensive but nice material always carries an incredibly steep price tag.

Alexandrite was originally found in Russia (hence the name as it was believed that the first piece was found on one of the birthdays of Czar Alexander) but sources in Sri Lanka and Brazil are now producing material as well.

In gemology, stones that do things like change color or have stars in them are known as stones with phenomenon. Personally I think alexandrites can simply be phenomenal stones. It is a stone however, that requires the purchaser to have an appreciation for the unusual, and is not neccessarily the most attractive of stones. While high quality alexandrite may achieve a rich purplish red color there is always a brownish tinge to this color and while people often wistfully say that the green approaches emerald green in tone, the color is less like emerald and more like tourmaline. In reality, even fairly expensive stones will have a muddiesh color tone to them and sometimes, under some lighting situations, the two colors will sort of blend together, again leaving a somewhat blurry image. But fine material can be truly astounding (and is exceedingly rare). One of the most beautiful stone I ever saw was at the Tucson gem shows about 25 years ago where one of the dealers had a magnificent 15 or 20 carat stone that had a huge color change and was beautifully transparent. I believe that the price was somewhat over $100,000 for the stone at the time (this was 25 years ago mind you!).

It seems that the people who know about, and love, this stone always tend to be collectors. I have one customer who owns 5 alexandrites that she has purchased from me. Another customer, who is mostly a gem collector, also has one he got from me. It is, however, an expensive habit. You can generally expect to pay between $5-10,000 per carat for decent one carat size stones. Larger stones are extremely rare so as soon as you get into the 2 ct. or bigger range the price range will skyrocket.

If you are interested in owning these stones here are the things to watch out for:

1) If the stone doesn't exhibit color change it isn't an alexandrite, it's just a chrysoberyl. There are many gem "dealers" on the Internet who sell stones they claim are alexandrite but they don't have any color change so they really can't be called that (I have seen a plethora of these stones show up in the last few years).

2) There are synthetic (man made) alexandrites that are in the market that are extremely hard to detect. You need to buy from a reputable source. If it sounds too good to be true it probably is. Interestingly, synthetic alexandrite is not a cheap stone to produce so the pricing on these will be higher than many other synthetics, which often means that they won't be so much cheaper than the natural that you would immediately be aware that it is a scam.

3) For many years, synthetic color change corundum (sapphire) has been on the market and was originally marketed as alexandrite because it had a color change. The colors are usually different from an alexandrite and after you've seen a few they are easy to identify. So if someone comes to you and says they own a really big alexandrite, most likely they are talking about synthetic corundum. I don't get as many people in with these as I used to, but over the years I have had to deliver the disappointing news to many people who said their mother/grandmother/great uncle/great grandfather swore to them that this was an alexandrite, that in fact what they had was a pretty much worthless bauble.

4) As with any expensive material there are always scams waiting to happen. Lately there have been a number of incidents in which jewelers have been approached by people (I actually had an email conversation with one myself) with large (ostensibly) alexandrites (among other stones) who will claim a variety of misleading things in an attempt to sell the pieces. They will say things like: oh, this stone is so valuable that no gem laboratory will identify it. Or that it is so valuable that they can't ship it to a gem lab to be identified. This is a load of hogwash. Any reputable gemological laboratory will identify any size gem material. As a matter of fact, they love to get in large, unique gem material because it increases their knowledge of what is available. And anything of any value can be shipped through a variety of means, and if they don't want to trust a shipper, surely if you have something worth so very much money, you can afford a trip to hand deliver the stone to a gem lab.

5) While it isn't absolutely necessary, it does help to have certificates from a reputable gemological laboratory on any major alexandrite purchase.

6) Know your source. Work with someone like myself who has both a Graduate Gemologist degree and has been in business for a long time. If they are a member of the American Gem Trade Association or Jewelers of America it helps as well. There are just far too many fly by night operations who are just out to make a quick buck and the Internet has expanded their numbers exponentially.

21 comments:

  1. Thank you! Very informative and cleared up a lot of questions I had.

    Thought of one more, though not as directly relevant to your business, as you don't sell silver items. Curious if you have any comments on polishing silver jewelry and/or keeping it untarnished in the first place. I believe it's supposed to be best to keep silver items in silver cloth as polishing essentially damages them; but I have some that have gotten tarnished and dread the thought of sitting down and trying to polish all their tiny little crevices. Any advice on getting and keeping them shiny?

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  2. Hi
    I have what I believe to be an Alexandrite that changes color and what I find interesting is it changes to an orange color under a black light. Does sound anything like what a Alexandrite would do?
    Thank you
    Lois

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  3. Hi Lois,
    I'm not sure how alexandrite responds specifically to your black light because I don't know what wave lengths it operates with. However what I can tell you is that under both long and short wave ultraviolet light alexandrite will fluoresce a weak red color. Some synthetic sapphires fluoresce a yellowish color under ultraviolet light so it is possible that you have a synthetic corundum (as I discussed in the article). If the stone is substantial in size that is probably what it is however I suggest you to take the stone to a gemologist for confirmation on what it is.

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  4. Laurel,
    I'll try to get to the issue of cleaning silver in another post.

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  5. I purchased a large amethyst or so I thought after seeing it change colors in light I researched it and it could possibly be alexandrite. I would love to send you a few pics of it under different lights if you could take a look.My email greek157@hotmail

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  6. I can assure you that if it is a large stone it is not an alexandrite. What you actually have is a synthetic sapphire. This material is quite common (and cheap) and was mistakenly sold by many jewelers as alexandrite for a long time. You should look at item #3 in my blog posting on this stone above.

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  7. My grandmother received a ring back in the 40's as a gift, and gave it to my mother because she hated how it kept changing colors. My mother was thrilled! I am now in possession of it, and have been researching all about the elusive Alexandrite. I am afraid of shipping it off, so will arrange for an in-lab visit. What I would like to know is, would something that I can at least date to the 40's/50's with a blue-green to purple-pink color change be a synthetic? Based on what I have found, it is about 2.2 carats. Thank you! : )

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    Replies
    1. Synthetic sapphires were first created in the 1890's so yes by the 1940-50's there were many of them around. Most likely, in that size range, you have a synthetic sapphire unless your grandmother was dating a very wealthy gent at the time who gave her the stone. I am happy however to look at it anytime and tell you what it is. Just don't get your hopes up.

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  8. Everything you're doing is completely unnecessary. In less than 2 minutes, with my equipment, I can tell you if you have an alexandrite or a synthetic sapphire. Why don't you just stop in and I can keep your head aches from getting worse.

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  9. I think I will! Do you conduct a refractive index and spectroscope test? Does the stone need to be removed from the setting to do so?

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  10. I do a refractive index test and usually the stones don't have to be removed from the setting.

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  11. When my mom comes to visit me in Boston this fall, I would love to bring her in with me to have the stone looked at. I will contact your office for an appointment at that time. Thank you!

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  12. My gem is greenish blue in daylight and florescent, bluish purple in house light. Magenta like in uv light. And very, very old. Any ideas what it could be?
    Thanks'

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    1. Gems that exhibit bluish purple/greenish blue color change are synthetic corundum. Alexandrite exhibits a greenish/reddish color change. Read my replies above that deal with age of the stones.

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    2. The picture that is at the top of this blog better depicts the colors i'm seeing. The green in daylight and the other color in house light. Although depending on outdoor light there are different shades of that green and blueish purple. Is that picture synthetic corundum?

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    3. The picture depicts natural alexandrite. The question I would ask you however is how big is your stone? If the stone is on the large size the likelihood of it being natural alexandrite is low. If you read my latest article there is more information about alexandrite: http://spirerjewelers.blogspot.com/

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    4. My stone is on the large side, held by 14k gold. Just a plain gold mounting. Late 1800's. My problem is, if not Alexandrite, what is it, what else is that green in daylight? If you have an email that i can send pictures, let me know. Thank You!

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    5. My email is daniel@spirerjewelers.com

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  14. I have a 10k gold ring with a large stone in it - I believe it's vintage, but not sure. The stone is lavendar in some lighting and bluish/lavendar in other lighting. If I look through the center of the stone toward the light (there's an open spot in the setting), the stone is yellowish. It also tends to pick up coloring from its surroundings sometimes. What kind of stone do you think it is?

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  15. Hi Holly. First of all what I can tell you is that if the ring is 10k you do not have an alexandrite. Alexandrites are extremely expensive and would not be put in a 10k ring. However I can't tell you what you do have because I don't have the stone in front of me. To do a proper analysis of a gemstone I need to be able to actually see the stone and take a variety of tests on it. No legitimate gemologist would guess at what you have from a vague verbal description of the color. If you are in my area you are welcome to come in and I can look at it. If you're not you can take it to any AGS (American Gem Society) jeweler in your area and their gemologist can tell you.

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