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  1. #1 microscope repair video 
    Forum Freshman davegimchee's Avatar
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    Hi everbody~

    I am new to this forum and I am not sure where to put this but since earth science is as close as you can get to gemology I will place it here. I am a gemologist by trade and I recently posted a video on my blog that might be interesting to those of you who have microscopes. It is a basic maintenance routine that I have demonstrated on video. It includes a list of tools and on the video there are step-by-step instructions.

    Although this video was made for a gemological microscope with a darkfield well, the basic concepts are applicable to many different kinds of microscopes particularly those with a rack-and-pinion focusing mechanism.

    I would be grateful to anyone who stopped by, and I am also looking for any criticism or comments that anyone would like to share.

    You can watch the video at my blog:

    http://tiptopgem.com/


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  3. #2 Also- gemstone questions 
    Forum Freshman davegimchee's Avatar
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    If you have any questions about gemology I would be really happy to answer them- or at least try. There is a lot to know and I don't pretend to have all of the answers but I will give it my best shot!

    David Fortier, GG (GIA)
    Staff Gemologist
    tiptopgem.com


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  4. #3  
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    Will you answer them here or on your blog?
    Disclaimer: I do not declare myself to be an expert on ANY subject. If I state something as fact that is obviously wrong, please don't hesitate to correct me. I welcome such corrections in an attempt to be as truthful and accurate as possible.

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  5. #4 your call 
    Forum Freshman davegimchee's Avatar
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    It's your call- I think if I want to contribute to your forum then any that come here should be answered here. And I do want to contribute!
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  6. #5  
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    What exactly does one do as a gemologist? Does the "IN" box on your desk contain just a pile of precious stones that need identification ? =P
    Kidding aside, what does being a practitioner of gemology entail?
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  7. #6 yes, a big pile of gemstones! 
    Forum Freshman davegimchee's Avatar
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    LOL. Well, sometimes that happens!

    The field is so vast- I guess it would be like asking "what does a mechanical engineer do?" But in my case, our company is small so I wear many hats. There are only three of us running tiptopgem at the moment so my days are full of customer service correspondence via email and instant messages and phone calls.

    Also I list stones on eBay and have a lot of contact with customers who buy stones directly from our company. This means taking a lot of photographs of the stones and writing descriptions of them, and deciding whether a stone is slightly purplish-red or very slightly purplish-red. Small differences like this can mean large differences in value so it's important to get it right! For the average colored stone dealer on eBay that is not such a big deal because they are selling more common stones to new collectors. But our specialty is rare stones and our customers are the more advanced collectors who have a lot of experience, and also other gemologists who are buying for themselves or for clients. They are well-educated and their knowledge means that I have little room for error.

    The other end of it is travel and buying, which I really enjoy. I live in South Korea, but the largest colored stone wholesale market in the world is in Thailand. It is in a small town 4 hours by bus southeast of Bangkok called Chanthaburi, not far from the border with Cambodia. I travel there at least every two or three months to buy stones. You can actually see a video on my site of the gemstone market. It is a magical place to a gemologist or colored stone dealer or collector. It is our "heaven" as about 70% of the colored stones that are sold in Western markets travel through Thailand, and the majority of these go through Chanthaburi.

    Usually when I travel to Thailand I will spend the weekdays in Bangkok with my regular contacts who handle rare stones, then I will go to the market in Chanthaburi which is open Friday and Saturday. Depending on what orders I haven't filled and/or how much of my budget I have not spent, I may travel back to Bangkok and start the circuit over again. My costs are fixed pretty much- the plane ticket is the largest expense- so the greater the portion of my budget I can spend on stones for each trip the better it is. If I buy one stone, the customer who buys that stone has to pay for my whole trip! But if I buy 100 stones, each person only pays for 1% of my trip. That's more reasonable.

    Actually, on a typical trip I might only buy 200 stones. That is a very, very tiny number compared to the high volume, low quality dealers who make up 99% of the colored stone market. From the beginning my partner and I decided that we wanted to deal in quality stones and that has been our niche. It also makes the business a lot more fun for me because I am a collector myself and I have a lot of appreciation for rare stones.

    Once I come back with the stones, there is a lot of time weighing and measuring each one, adding them to the database, and then doing clarity grades using the microscope set at 10X. After that I usually take photos and write copy describing the stones that will be put on eBay, and I actually do the listings. But the majority of our sales are direct so that means I don't have to do listings or take photos for each one. When I get a request for something, and I have the stone in the weight and size that a customer is looking for, I will do some photos and a description and send it along to him or her.

    Things are about to change quite a bit as we are opening a buying office in Thailand which means I will be there full-time. I am really excited about that both because I like the country a lot, and it means that I will have greater access to more stones as a collector and as the buyer for the company. So our customers will really benefit too.

    Also literally every single day is spent with continuing education for me since the trade and the science moves very quickly. There are regularly new treatment methods for colored stones that greatly affect their value. I need to be aware of all of the latest techniques if I am going to be able to recognize these treatments at the marketplace before I buy. Mistakes are very expensive in this business. I spend time reading the latest forum postings on gemology forums and sometimes correspond with other dealers or gemologists about these treatments.

    Wow, I feel so tired now. LOL. Holler if you have any questions!

    Dave
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  8. #7  
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    Thanks much for that detailed description of your work! I was just wondering, do you get the whole variety of precious stones from Thailand?
    Disclaimer: I do not declare myself to be an expert on ANY subject. If I state something as fact that is obviously wrong, please don't hesitate to correct me. I welcome such corrections in an attempt to be as truthful and accurate as possible.

    "Gullibility kills" - Carl Sagan
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  9. #8 kind of! 
    Forum Freshman davegimchee's Avatar
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    My pleasure! We don't see much emerald, which mostly comes out of South America although there are some newer sources in Tanzania, Zambia and Zimbabwe. Because of Thailand's relatively easy access to the gemstone-rich sources of Sri Lanka, India, the Middle East and Africa- and the low-cost transportation between Bangkok and those sources- there is a very wide variety of stones in Thailand. Also the Chinese Thais have practiced aggressive source-control of mining operations in many countries. As corundum (blue is sapphire, red is ruby) sources became depleted in Thailand the cutting houses and heat-treatment facilities wanted to stay in business. Many of these individuals secured rights from mines overseas and continued to import rough gemstone material to Thailand. Sometimes they bought the whole mine, sometimes they bought the production for life, or they made arrangements with mine owners to be the sole outlet for the mine's production. Yet other Thai people established buying offices in these mining regions to ensure that the "rough" continued to flow through their businesses in Thailand. It's a really fascinating business because it rolls a lot of interesting disciplines together like politics, social science, geography, of course earth science, and also entails one of my favorite concepts- beauty.
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  10. #9  
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    Fascinating. Is any significant portion of this market driven by commodity trading, in the vein of buying and selling stocks? I'm sure diamonds are traded this way, but the rest of the gamut of precious and semi-precious stones dont exactly have universally accepted grading sysetms. I can imagine it would be hard to maintain or increase the value of your investment if nobody can agree on it's value.
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  11. #10 you understand... 
    Forum Freshman davegimchee's Avatar
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    I think you have a good grasp of this. Yes, there is no commodity-style trading because there is no universal standard. It is even hard to agree on basic things like color. I will say that a ruby is slightly purplish red and medium dark tone, and someone else will say no, it is very slightly purplish red and medium tone. I will say that it is deeply saturated, and another dealer might say "well, it is reasonably well saturated. the term 'deeply' might be going overboard'." So there is always disagreement over value factors like tone and saturation and hue- which keeps people from agreeing on prices.

    Also one dealer might sense weakness in the market for a particular stone- say a Ceylon sapphire over 3 carats, in cornflower blue. So he might price his stone at a 10% or 20% premium. But another dealer might have just sold one from his safe, and went to the market and got lucky to buy a couple more. To him, the world is rolling in cornflower blue sapphire over 3 carats! He might discount it. Supply is not plentiful in colored stones the way it is in diamonds, and there is no universal methodology or system in place to judge supply.

    A good example is blue tourmaline. When I see a parcel of blue tourmaline, I get excited. But I don't want the seller to know- and the last time I bought a parcel I paid a reasonable price for it. Now he and I don't agree on something. He thinks blue tourmaline is plentiful, and I think it is rare. Maybe he has seen a lot lately, and I have not seen much at all. If I can sell it at a profit, then I am right for my market. And I guess, in a way, his ideal is the same. If he can make money, it's OK. But if he knew how excited I am to see his blue tourmaline (we call it indicolite) he surely would charge me more. His starting price would be higher.

    It's a hard business to learn I would say because you have to be able to make mistakes to learn. And some people are not well-financed going in and they are so afraid to make mistakes that they stagnate. They only make very conservative buys at low prices so they never have quality stones that people are willing to pay for- and that they can profit from and use the proceeds to grow the business.

    On the other hand, if you are crazy about stones you would be crazy to do anything else. Especially if you love to travel and are flexible about how you live, what you eat, and what kind of toilet you use! LOL. If you are adaptable you can make your way in this kind of trade and have a lot of fun in the process.
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  12. #11  
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    Ah, thanks for the clarification. When you go gem-hunting, are you generally dealing with raw stones or cut stones? Which do you see more demand for from your clients?

    Also, I visited the link provided in your opening post and all I'm getting is a placeholder page saying "Welcome to the future Website for tiptopgem.com".
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  13. #12 alternate route! 
    Forum Freshman davegimchee's Avatar
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    ahhhh!!!

    Startlogic is down again. No surprise. You can see my page here:

    http://tiptopgem.wordpress.com/

    I only buy cut stones; rough is just an entirely different ballgame. I may do rough in the future but that will mean basically starting over in terms of assessing quality. I will benefit from my customer base and that will help turn inventory over after it is cut, but you don't just start buying rough and do it well unless you have a very good tutor who has decades of experience to guide you through it. Even then, you will have to make your own mistakes and learn from them. I guess with a mentor the idea is to learn from his or her mistakes and avoid them- which means you start with a leg up.
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  14. #13  
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    Wow, quite a bit of information on there, slowly working my way through it =)
    I had a question on parti-color tourmalines, specifically about what causes the color bands. Looking at electron microprobe data from one, I see increased amounts of Bi<sub>2</sub>O<sub>3</sub> in the pink bands and Na<sub>2</sub>O in the green rinds, but I also see pictures of tourmalines with brown and yellow bands. Are specific elements responsible for the bands, or is it simply a chemical crapshoot during crystallization?
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  15. #14 Chemistry?!? 
    Forum Freshman davegimchee's Avatar
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    Well, we get the basics of gemstone chemistry when we study gemology but a laboratory gemologist would be able to give you a more meaningful answer than I can certainly. But if you want to see a ton of chemical formulas that relate to tourmaline, take a look down a ways on this page:

    http://www.mindat.org/min-4003.html

    Hope that helps answer your question! I could, of course, simply get out my electron microprobe and compile some data for you...LOL. If this doesn't answer your question, or if you need more information to make sense if it give me a holler! I will do my best!

    Dave
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  16. #15  
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    Thanks Dave, I'll check that out. It's not a huge deal, just casual interest, so no need to break out an electron microprobe, hah. =)

    One thing I have always had difficulty with is visualizing carats. Hearing a particular stone is say, 2 carats, is completely meaningless to me. Is there a handy mental device you use to associate a particular scale of mass or size to a carat value, or does one just need to be exposed to many different sized gems over time to get a good sense of the magnitude of a carat?
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  17. #16 the misunderstood carat 
    Forum Freshman davegimchee's Avatar
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    Oh, the carat. Poor thing. Nobody gets it. First, it is a unit of weight. If you have five carats, you have a gram. That's easy. It gets harder because a 6mm diameter round diamond will not always weigh the same! Some are cut with different proportions. They might be taller and thinner than the typical 6mm stone (or short and fat), so it's tricky to predict the weight. Couple that with the fact that colored stones are different densities, and you see that you can have many 6mm stones that all have different weights. And do you get used to this? No, not really. Well, kind of. If you deal a lot with one particular stone over a long period of time I think you may be able to develop an eye for it. But for all colored stones, with all their different densities? No.
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  18. #17 out of questions? 
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    Are you out of questions? I was just getting warmed up! LOL




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  19. #18 Re: out of questions? 
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    Quote Originally Posted by davegimchee
    Are you out of questions?
    Specific questions, yea. Theres a treasure hoarde of information locked up in that head of yours that I'd love to know, I'm just not sure what to ask; it's like the tagline from I-Robot: "You must ask the right question." One doesn't often get the opportunity to play 20 questions with experts, expecially in fields like gemology.

    Maybe I'm grasping for questions that are too specific, so I'll take a step back. Are there particular geographic regions that are responsible for producing the bulk of the worlds stones, or is it a random scattering of geographic conditions and locales?
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  20. #19 gemstone mine locations 
    Forum Freshman davegimchee's Avatar
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    That's more like it. And to answer your question, there are many locales that bear a concentration of gemstone deposits and mines. Some of the more famous ones are the tsavorite and tanzanite mines in Tanzania and Kenya, the huge concentration of gemstones of many types in Brazil, and the ruby and sapphire-rich areas in Burma.

    The United States has some peridot in Arizona and sapphire in Montana, but of these only the peridot is commercially important. There isn't enough sapphire coming out of Montana to make much of an impact on such a large world market. Speaking of sapphire, there is also a lot in Madagascar. There is also a substantial amount of ruby coming out of Madagascar now- though not nearly as much ruby as comes from Burma.

    Brazil is not the only South American country with a sizable and commercially important gem industry. Colombia produces some of the world's most fabulous and expensive emerald. There are also emeralds from Tajikistan, Russia, India, and North Carolina- but Colombian emeralds are the most significant.

    That's the thing with colored-stone deposits- they are in many places but only a few areas are producing good material consistently over a long period. It's not like diamonds where you find a "pipe" and you invest millions of dollars on it and mine it for decades or even a century- most colored stone deposits are pick-and-shovel affairs. Small-time miners working in tough conditions to make a living work a discovery for days or weeks or if they are lucky- longer. But to work one spot for years is rare. Usually they are moving around looking for the next big strike.

    The Mogok valley in Burma is famous for the best ruby in the world, but it does not all come from one spot! There is the arduous task of breaking up the marble that contains the precious gemstone- but to do such work one wants more than a hunch that there is something in this precise spot! But no guarantees are available. So teams of workers move and scout and when they hit paydirt a lot of labor is concentrated in that area until there seems to be no more ruby hiding in the marble.

    Sri Lanka is another good spot for ruby and sapphire- which, by the way, are the same mineral with different coloring agents. Some of the most beautiful corundum comes from Sri Lanka- particularly famous are the "cornflower" blue sapphires. And the padparadscha sapphires (orange/red) are simply to die for!

    It used to be that diamonds were the domain of the mining companies in South Africa, most of which fall under the DeBeers umbrella. But things are changing quickly, and DeBeers is a shadow of its former self. The diamond production from Australia, Canada, and Russia is significant and has had an enormous impact on the world market and on DeBeer's monopolistic power as well.

    In two or three weeks I will be heading to Thailand on another buying trip and I will try to remember to get back here and give you some of the latest news. In this industry, things change so quickly. One source dies and a new one is found. Stones that were once rare become plentiful. Stones that were all over the place are nowhere to be found. And treatments is another issue- the Thais are always finding a new way to cook a stone to make it beautiful!

    They say a stone needs beauty, durability, and rarity to make it a gem. That makes treatment a real problem because while the stone is beautiful and durable, since it was an ugly stone when it came out of the ground and it is beautiful now- it has lost it's status! Chemically-enhanced stones are just not rare. Ugly stones are everywhere so who wants to buy such a common item, even if chemicals made it beautiful?
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  21. #20 Re: gemstone mine locations 
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    Quote Originally Posted by davegimchee
    Chemically-enhanced stones are just not rare. Ugly stones are everywhere so who wants to buy such a common item, even if chemicals made it beautiful?
    How difficult is it to detect whether a stone has been altered? Certain enhancement methods require the seller disclose the treatment to prospective buyers, but I would imagine this is rather difficult to enforce, especially with the countless small-time gem peddlers I see in some of your photos.
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  22. #21 meat and potatos 
    Forum Freshman davegimchee's Avatar
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    That's the heart of gemology today for many of us. Has this stone been treated? How has it been treated? Is this treatment acceptable and how does it affect the value of the stone? Did my supplier (whether a walker at the market in Chanthaburi or a guy in a fancy office in Bangkok) disclose the treatment to me, and how should I disclose it to my customer?

    Ruby is a good example for us to use. Let's say we have four rubies and each is over one carat, but not by very much. They weigh between 1.01 and 1.04 carats. (Remember the poor, misunderstood carat- the little guy is a fifth of a gram.) These rubies are all for sale, and they are all really beautiful color. They are medium to medium-dark tone (that is the lightness or darkness of the stone) and are a very saturated red color. Think of opening a can of red paint- if you don't add water to it, it is highly saturated. It's very, very red! Add some black paint to make the tone darker. Now you have medium-dark, saturated red. EXPENSIVE! These stones are clear (not cloudy) and very sparkly (good cutting). Get my checkbook! Sorry, cash only at the market and no refunds. So you better be sure.

    Stone #1 is from Mogok, Burma and is unheated. It has not been treated in any way- it is right out of the ground, except for the cut and polish. This is the stone of your dreams. WOW.

    Stone #2 is also from Mogok, Burma. It is heated only. Just plain old-fashioned heat like they have been using on stones since the ancient egyptians. No worries here. Still, not quite as valuable as the stone above which was not even heated.

    Stone # 3 is from Mong Hsu, Burma. This is a different mine, and the material tends to have fissures, or cracks, that reach the surface of the stone. This ruby was heated in borax. The ruby along the walls of the fissure was dissolved, formed a "flux" with the borax, and as it cooled this flux was redeposited in the fissure. Presto, the stone is beautiful, durable, and not nearly as expensive as the stones above. This is done with virtually all Burmese ruby today, because virtually all Burmese ruby comes from Mong Hsu.

    Stone #4 is similiar to the stone above- at least it was when it came from the ground. The problem here is that the cracks, or fissures, are big and wide. You can't heat it in borax because the cavity is too big to fill. Leaded glass to the rescue. The stone is heated in a mixture of glass and chemicals and the fracture is filled with high-lead content glass. It is beautiful. It is not durable, nor is it rare. This stone is not expensive, and it shouldn't be. It will last a few weeks or many years depending on how you treat it. Never put it in an ultrasonic cleaner like your jeweler uses! Make sure your jeweler knows he has to remove it before he works on your prongs with a torch!!! That glass will run right out!

    Unheated can be fairly straightforward to detect. There are needles and small crystals of other minerals in many rubies that have one appearance before heat, and a totally different appearance after heat. Sometimes you can even tell about what temperature was used- to an extent.

    Heated stones have partially or totally melted crystals, and there may also be stress halos around those crystals because as they expanded with the heat, they had no place to go! The pressure tried to escape and made some tiny cracks in a circle around the crystal inside the stone. These are fun to look at- it's like art. The needles that were there, and straight and continuous- are now broken and dotted. They seem to be shadows of their former self after the heating.

    The flux-healed are pretty easy to tell with a microscope. They leave little channels behind in the stone that look sticky or drippy. Often there will be little bits of flux that is trapped in these channels.

    Glass has bubbles. Natural stones (overall) do not have bubbles. Glass-filling is easy to detect. Also, since these fissures (and the glass that fills them) reach the surface of the gemstone, you can see a luster difference between the actual ruby and the glass filling. Ruby reflects light differently than leaded glass.

    Sapphire has the problem of "diffusion". This is cooking it at very high temperatures (1800 C or so) in the presence of a light element like beryllium. The be penetrates the stone and creates a beautiful blue color. It's best to send a stone like this to a laboratory if you aren't sure whether it is cooked in chemicals or not. A third-party certification is always good for any colored stone, but especially for sapphire- and it's not a bad idea for ruby!

    You are getting better at this question thing. LOL
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  23. #22 Re: meat and potatos 
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    Man, Im gonna need to start writing this stuff down, hah. =)

    Quote Originally Posted by davegimchee
    They are medium to medium-dark tone (that is the lightness or darkness of the stone) and are a very saturated red color.
    What other qualities are considered when appraising a stone? I've seen you mention mass, color, luster, cut, and the type of enhancement (if applicable). I can imagine the presence or absence of imperfections in the gem is also considered. Are there others?
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  24. #23 value factors 
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    In the trade we call these value factors. The biggest are color, cut, clarity, and carat weight. Provenance can also be quite important.

    Color is king, and that is why I put it first. The finest "pigeon's blood" ruby can have fair clarity, a lousy cut, and be rather small- but if it is that special color it can be worth a fortune.

    Cut is based on how much light is returned through the crown of the stone. Light goes in through the crown, or top, and reflects off of the inside of the stone at the bottom and sides- called the pavilion. The more light that comes back out the top, the better the cut. This is seen as "brilliance" or sparkle. Some stones show a ton of sparkle due to a great cut, and some show very little due to a bad cut. It's all about the angles that the cutter chose.

    Clarity is not as important in colored stones as it is in diamonds. With diamond there is a lot of emphasis on the largest or most prominent inclusions that set the clarity grade. And most people shop for clarity first. But in colored stones, it is not so important for a stone to be totally free from inclusions, or even totally free of eye-visible inclusions if it has the right color.

    Carat weight- what you called mass- is critical. There is a big difference in price per carat of a one carat stone as opposed to a two carat stone. A two carat ruby is much more than twice as rare as a one carat stone, so the two carat will sell for more than twice as much. If a one-carat ruby is $2,000, a two-carat ruby could be $6000 for similar value factors.

    Provenance is important in many cases. If a laboratory can establish that a stone came from Mogok, Burma then that ruby will be worth much more than one from Madagascar, Africa even if the cut, clarity, carat weight, and color are identical. Mogok is known as the most highly acclaimed ruby source in the world. Now not every stone that comes from this valley is so fabulous- but people will pay for the provenance.

    Luster is not really a value factor, but it brings us to another one which is treatment. In the previous example we used luster to see that a stone was filled with glass. The glass-filled cracks or fissures have a different luster than ruby itself. If a stone is filled with glass it better be beautiful and cheap. Otherwise the market will not tolerate it. But it should be noted that there is a market for a beautiful one-carat ruby that costs a few hundred dollars. The people who specialize in these treatments are choosing that sector of the market.

    The diffusion treatment that we discussed is another way for folks to get a beautiful sapphire for low cost. There is nothing wrong with any treatment as long as it is disclosed. Many dealers have failed to disclose treatments in the past which hurts our industry. Honesty is always the best policy if you need the public trust, and we as colored stone dealers really need it.

    Now we've hit our stride. Let me know if this brings up other issues about which you are wondering! I am happy to have a forum to answer questions.
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  25. #24 Re: value factors 
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    Quote Originally Posted by davegimchee
    Let me know if this brings up other issues about which you are wondering! I am happy to have a forum to answer questions.
    Thanks, I must say, it's been a pleasure having your input. =)

    I'm surprised that the place of origin plays a significant part in the value of the gem. I suppose this is along the lines of 'branding' in market goods, where people are willing to pay a premium for 'designer' products that may or may not be any better than a lesser-known competitor.

    When you go gem hunting, what kind of tools do you usually bring along to appraise stones, if any?
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  26. #25 origin 
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    My pleasure!

    Origin is a funny thing. Sometimes inferior stones will bring high prices because they are from the right place. And while many nice rubies come from Mogok, Burma- many ugly ones come from there as well. When a very beautiful stone comes from Africa, it is hard to get a price that approaches that of a Burmese ruby. Likewise with emerald- you want a Colombian stone if you are into that kind of thing, and you want the Muzo mine. Yes, the trade even prefers a particular mine within a country!

    I encourage people to pay for beauty and not for origin. In a way it is like designer goods- but surely there are benefits to a Louis Vuitton bag. You do get a very stong, well-stitched item. It has a great warranty. When you take it back to the store with a problem, they treat you like royalty. And I suppose you get bragging rights. Surely with a Mogok ruby, you do get bragging rights as well!
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  27. #26  
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    Quote Originally Posted by davegimchee
    Surely with a Mogok ruby, you do get bragging rights as well!
    I would imagine this also opens the door for counterfeiters to claim their rubies are authentic Mogok rubies, consequently raising the value of their wares by a hefty premium. Sounds like it would be difficult to disprove, as well. A Louis Vuitton bag has physical qualities that make it stand out from counterfeits, but the if quality of gems can vary at a single location, I think it would be hard to define a Mogok ruby without extra leg-work to trace the origin.

    For gemstone veins in general, how are stakes claimed? By that I mean, do you see a lot of independent prospectors running about digging for stones, finding a vein, and then milking it dry, as opposed to larger, more organized prospecting groups that oversee teams of diggers? Or perhaps it works more like turn-of-the-century oil prospecting, where entrepreneurs or wealthy conglomerates buy up promising tracts of land and try to find something valuable in them?
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  28. #27 you got me!! 
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    You got me on that! As far as mining claims and methods and organizations involved in extraction, you should ask someone who has been around the mines a lot. Someone who comes to mind is Vincent Pardieu, who writes fieldgemology.org. I sent him a message about this thread and hopefully he will stop by and give you some answers. He has traveled extensively to mines all over the world and is highly respected for his expertise and his willingness to share it! He's also a nice guy (for a Frenchman).
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  29. #28  
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    Quote Originally Posted by davegimchee
    I sent him a message about this thread and hopefully he will stop by and give you some answers.
    Thanks, that'd be fantastic =)

    How about synthetic gems? Do you see a lot of them in your corner of the world? Do people try to pass them off as authentic natural gems, and are there enough differences between synthetics and those formed naturally that you can tell what you're buying?
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  30. #29 sythetics 
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    Oh, gosh yes. There are tons of synthetics at the market in Thailand. And people do try to pass them off as natural, mined stones. Are they easy to separate from natural gemstones? Well, yes and no. They are always coming up with crafty new techniques to make synthetics look natural, but if you are experienced buying stones, and you keep up on all of the latest news in the gemological world regarding synthetics and treatments, you definitely have a big advantage over the guy who doesn't keep up. Also you have to be skeptical about every stone and don't make any assumptions.

    Some of it is common sense as well. If it seems too good to be true, well, it probably is. It is also said that the closer you get to a mining area, the more synthetics you will see. There are plenty of peddlers around mines (and cutting centers like Chanthaburi) who can invest a tiny little bit of money on some synthetic stones and if they can fool one person per week they can live well. That is a big temptation.
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  31. #30  
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    Tough market out there =)

    So how did you get started in gemology? What was the draw for you?
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  32. #31 my start 
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    I always loved rock and minerals as a kid and was an avid collector and reader for a very long time. I never did figure out what to do with a degree in European History, and I ended up working in the retail end of the jewelry business. I did that for about ten years, got tired of it and moved to a federal job. The job took me out to Hawaii where I lived for a couple of years. I'd grown fond of a Korean woman there but that was not meant to be- still, I reasoned that if I moved to Korea most of the women there would be Korean. That was the beginning of the end! LOL

    I got a job teaching English at a language school in Korea, and later taught for a couple of years at a university. I traveled Vietnam, Thailand, Cambodia, and the Philippines and bought stones here and there for fun. While my fellow lecturers were studying in their free time, and with their free money, I thought I should do so as well. But what to study? I didn't really want a master's degree in anything. So I decided to sign up to study with the Gemological Institute of America for my GG diploma- that's Graduate Gemologist. I did a lot of the work at home, built my own basic gem laboratory, and during my vacations I would travel back and forth between Korea, the U.S., and Thailand doing my lab work and also doing some buying and selling.

    Before I finished the gemology program I decided it would be feasible to make a living at the business so I didn't renew my contract at the university where I was teaching. I'm really blessed in that I get to do something that I love to do- even if I don't make a lot of money. We are a small company with only three people now, but we are growing and the future look bright. We will open a buying office in Thailand early next year and that will be my post. How exciting!! It will be wonderful to be in the thick of the action all of the time instead of flying back and forth every couple of months. It will save on expenses too- it's not cheap flying when oil is $140 per barrel!
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  33. #32  
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    Quote Originally Posted by Frenchi
    I would imagine this also opens the door for counterfeiters to claim their rubies are authentic Mogok rubies, consequently raising the value of their wares by a hefty premium.
    Sounds like it would be difficult to disprove, as well. A Louis Vuitton bag has physical qualities that make it stand out from counterfeits, but the if quality of gems can vary at a single location, I think it would be hard to define a Mogok ruby without extra leg-work to trace the origin.
    Hi Frenchi,
    Well this is the job of gemological lab such as the one I'm working for to identify the origin of a given gemstone. Mogok rubies have some characteristics that rubies from other regions, even if they look similar, usually don't have...

    Quote Originally Posted by Frenchi
    For gemstone veins in general, how are stakes claimed? By that I mean, do you see a lot of independent prospectors running about digging for stones, finding a vein, and then milking it dry, as opposed to larger, more organized prospecting groups that oversee teams of diggers? Or perhaps it works more like turn-of-the-century oil prospecting, where entrepreneurs or wealthy conglomerates buy up promising tracts of land and try to find something valuable in them?
    It just depends of the country... In countries like Canada or Brazil many gemstones mines are usually controlled and operated by "modern type" companies. In countries like Tanzania, Afghanistan or Madagascar things are quite different.
    If you are interested by details about that you are welcome to visit the different pages of my website:
    http://www.fieldgemology.org/

    Hoping to have helped a little bit,

    All the best,
    "Travel addicted gemologist"
    www.fieldgemology.org

    Note: Any views expressed here are V. Pardieu’s opinions and do not necessarily reflect those of the Gübelin Gem Lab ( www.gubelinlab.com ) where he is an employee since Feb 2007.
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  34. #33  
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    Thanks Pardieu! I'll definitely read through your site. From looking briefly at your pictures, I'd say being a gemologist requires an appetite for adventure; that goes for Dave too =)


    Quote Originally Posted by davegimchee
    - still, I reasoned that if I moved to Korea most of the women there would be Korean.
    I'd say that was a pretty safe bet =) I won't say the thought hasn't crossed my own mind, anyway :wink:

    Quote Originally Posted by davegimchee
    I got a job teaching English at a language school in Korea...
    This seems to be a strangely popular thing to do, having known a few people who've done this personally. I hear mostly positive things about the experience.

    Quote Originally Posted by davegimchee
    So I decided to sign up to study with the Gemological Institute of America for my GG diploma...
    What kind of program is this? It it like stretching Geology class into an entire post-graduate routine? =P
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  35. #34  
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    Pardieu, I just read your section on the gemological properties of Panjshir emeralds, you write:

    It is interesting to note that the fuilds in these emeralds may contain a greater variety of minerals compared to what is commonly seen in emeralds from Colombia, which usualy contain only halite, while fluids in emeralds from Pakistan usualy do not contain any solids. Another interesting difference is the shape of the fluid inclusions:...
    Are these the type of differentiating traits you look for when attempting to identify a stone's place of origin?
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  36. #35  
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    Quote Originally Posted by Frenchi
    Are these the type of differentiating traits you look for when attempting to identify a stone's place of origin?
    Well first I would like to thank you for your interest in the writtings on my website...
    To answer you now specifically: yes but not only...
    When we work on origin determination of a gemstone, we are collecting of course information about the nature of the gemstone inclusions (it is a link to its geologic background) but we study also its chemical composition (trace elements and "ultra trace" elements can be useful), its spectra and in many cases also some more basic gemological tests.
    It is the combination of all these results which lead to us to think that a given stone might come from this or that mine.
    Of course to be able to provide an expert opinion (meaning an opinion based on scientific facts that you can explain...Not just an educated opinion or a feeling) the first thing you need is to build a very complete reference collection (composed of reliable samples) and to have studied and documented it thoroughly...
    This is the reason I travel the world to mining areas: To collect data about the difference sources of gemstones we provide origin determination.
    It can be difficult in some cases as gemstones can be formed in different places from very similar geologic conditions but in many cases we can provide an origin to a ruby, a sapphire or an emerald.
    If you are interested by the subject I recommend the reading of the following article trilogy:
    http://www.gubelinlab.com/Origin_Articles.asp
    Hoping to have helped.

    By the way my given name is "Vincent", not "Pardieu"...

    All the best,
    "Travel addicted gemologist"
    www.fieldgemology.org

    Note: Any views expressed here are V. Pardieu’s opinions and do not necessarily reflect those of the Gübelin Gem Lab ( www.gubelinlab.com ) where he is an employee since Feb 2007.
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  37. #36  
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    By the way my given name is "Vincent", not "Pardieu"...
    Ah, my apologies. I was originally writing Vincent as well, then I looked at your forum handle, saw the Pardieu in front, and went back and switched them around. Oh well =)

    Thanks again for the input. I'll read through the pdf's and get back to you.
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  38. #37  
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    Quote Originally Posted by Frenchi
    By the way my given name is "Vincent", not "Pardieu"...
    Ah, my apologies. I was originally writing Vincent as well, then I looked at your forum handle, saw the Pardieu in front, and went back and switched them around. Oh well =)
    No problem, it was just sounding funny to me...
    "Travel addicted gemologist"
    www.fieldgemology.org

    Note: Any views expressed here are V. Pardieu’s opinions and do not necessarily reflect those of the Gübelin Gem Lab ( www.gubelinlab.com ) where he is an employee since Feb 2007.
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  39. #38  
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    It almost seems like the process of determining a stones origin could easily become more expensive than the value of the stone. Is origin tracing usually done only on very expensive stones, or perhaps multiple stones? How do your clients justify the cost?
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  40. #39  
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    Quote Originally Posted by Frenchi
    It almost seems like the process of determining a stones origin could easily become more expensive than the value of the stone. Is origin tracing usually done only on very expensive stones,
    Usualy yes:
    Working seriously on origin determination has a cost as you need a good reference collection, highly trained gemologists and some powerful instruments (UV-VIS, FTIR, EDXRF, Raman, LAICPMS,...)
    Our report are not cheap for sure and this is the reason why we are mostly working on rubies, sapphires and emeralds regarding origin determination.

    Quote Originally Posted by Frenchi
    or perhaps multiple stones? How do your clients justify the cost?
    Well, in the market the value difference between a blue sapphire from lets say Pailin in Cambodia and Sumjam in Kashmir can be huge, even if the stones aspect can be quite similar. Then typically buyers are ready to pay a percentage of this price difference in order to check if the origin announced by the seller can be confirmed or not.
    It is all the time the same process: For years stones heated or not had the same value, but then when some dealers decided to pay a premium for unheated stones, a difference in value appeared in the trade and subsequently the labs were asked to check if the stone is or is not heated.
    In fact we are just trying to use some scientific tools identify properly what is what as a service to the gem trade.
    Hoping to have helped.
    "Travel addicted gemologist"
    www.fieldgemology.org

    Note: Any views expressed here are V. Pardieu’s opinions and do not necessarily reflect those of the Gübelin Gem Lab ( www.gubelinlab.com ) where he is an employee since Feb 2007.
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  41. #40  
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    I do want to contribute!
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  42. #41 Exploitation and the Gem Trade 
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    I've just posted an article called "Exploitation and the Gem Trade" and would welcome comments! You can find it here: http://tiptopgem.com/
    Great achievement is usually born of great sacrifice, and is never the result of selfishness.
    ~Napoleon Hill
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