Author Archives: Harry Bernard

Lighting and Grading Gemstones Part II

LIGHT UP YOUR LIFE

by Richard W. Wise, G.G.
© 2006

What is the best lighting environment to view gemstones? In part I of this post I discussed the various lighting options and the pros and cons of each. In part II I will write about the lighting some of the world’s foremost gem experts and connoisseurs choose to both view and evaluate gemstones.

Among the experts opinions differ somewhat as to which “daylight” Kelvin temperature is best but each accepts daylight as the standard. Stephen Hofer one of the world’s most respected authorities on colored diamonds, maintains that 5500K works best for colored stones and 6500K is best for diamonds both white and colored. In his lab, which is dedicated to the evaluation of fancy color diamonds, all grading work is done under 6500 Kelvin fluorescents. C. R. Beesley, President of American Gem Labs in New York, prefers Vitalite a bulb manufactured by The Duro-Test Corporation with a Kelvin rating of 5500. “Most people don’t do their homework”, says Beesley, “comparing color temperature isn’t enough…” Beesley tested more than twenty different light sources in the process of developing his Colorscan colored stone grading system to gauge their actual effect on gemstones.

In 1994 GIA completely revamped its color grading system for colored diamonds, shifting from Veralux, a so-called low UV lamp rated at 6200K, (see Secrets Of The Gem Trade, p.60, fn) which remains its standard for grading colorless diamonds to a 6500K average daylight fluorescent bulb for grading colored diamonds. The lamp is manufactured by Kollmorgen Corporation. GIA also uses a 6500K for general research purposes. The Institutes use of light of this Kelvin temperature is in no way an endorsement of the use of this type of lighting by jewelers. According to James Shigley, GIA’s Director of Research, 6500 was chosen because it is a recognized standard used by color scientists. Little or no thought was given to enhancing the beauty of gemstones.

Incandescent and quartz halogen lamps can be made to resemble daylight with the addition of a blue filter. Duro-Test currently markets a “super-white halogen” that does the same job. I conducted a series of experiments with the Duro-Test product and found that this type of lighting does wonderful things for blue sapphire, aquamarine and amethyst, but does nothing to reduce the muddy look in blue and green tourmaline. “Super-white” induces a distinctly overblue look in rubies and tanzanite takes on an odd blue/violet multi-color effect quite dissimilar to its appearance in any other lighting environment. In diamond, “super-white” overly enhances the yellow/blue luster of the stone.

The problem!, filtered light makes for unintended results. Unfiltered fluorescent lighting can exhibit a relatively balanced spectrum when graphed on what scientists call a “Relative spectral power distribution” curve. Filtered lamps show spikes in this curve which are areas of color deficiency.

Another type of lighting called Neodymium is currently being marketed as a “full spectrum incandescent”. According to Roger Schoenfeld, a lighting specialist with Durotest, this is really a standard yellowish incandescent incased in a special glass invented in Sweden, which reduces yellow and generates a spectrum richer in red and blue. Neodymium is not a bad choice. It is excellent for diamonds. Neodymium is a bit better than standard quartz for sapphire and aquamarine though not as good as “super-white”. All three sources suppress the violetish to purplish secondary hue of the finer grades of sapphire.

Compared to daylight, neodymium works well with ruby, amethyst, emerald and tsavorite garnet. It is no worse with blue and green tourmaline which seems to be a true day stone, i.e. it looks its best in daylight and in daylight fluorescent 5000-6000K. Pink & red tourmalines do fine in Neodymium “full spectrum”, it does not produce the brownish secondary hue that most pinks exhibit in standard incandescent but, rather makes them look violetish. Tanzanite looks about the same as with quartz light; bluer than stan
dard incandescent and without the otherworldly quality of “super-white”.

Three or four years ago, Tailored Lighting introduced a 4700 Kelvin MR-16 lamp which has the highest Kelvin temperature of any incandescent bulb and may be the best solution yet for interior lighting. The new Solux lamp uses a new type of reflector to boost the quartz halogen lamp into the daylight range. This technology produces lighting with a fairly even power distribution curve (CRI) that shows no spikes in either the red or blue areas of the visible spectrum.

In a short, down and dirty test, Solux worked well with tourmaline, reducing the muddiness produced by all other incandescent light sources. Sapphire and ruby also benefited from this type of lamp, showing they’re colors in true daylight fashion. Solux also improved the diaphaneity of tanzanite. On the down side, Solux appeared to add a gray component to aquamarine and pink topaz which reduced the saturation and flattened the color.

Changing lighting environments have always been a problem for both buyers and sellers. You buy in one light, sell in another. Traditionally dealers who do extensive buying outside their offices have relied upon comparison stones, stones of well known color, which they carry or wear on buying trips.

I use two fixtures with twin four foot fluorescent lamps to give an overall daylight environment combined with several of the new Solux MR-16 4800K quartz halogen lamps in my own laboratory which doubles as a salesroom and consider this combination to be the closest possible to a true daylight environment. I use Duro-Test Vitalite in one fixture and Kollmorgen 6500K average daylight in the other. The use of the 6500K is to compensate for the 4800K Solux, to kick up the Kelvin temperature of the overall environment towards 5500K.

The combination of of daylight fluorescent with Solux works acceptably across the spectrum of gemstone colors. The fluorescents create an overall daylight environment and the Solux MR-16 provides the punch. This lighting temperature gives a balanced daylight color rendering when compared to New England north daylight. Several years ago, a German firm, System Eikhorst, introduced a lighting system based, in part, upon my recommendations. It includes both daylight fluorescent and Solux fixtures.

When making a purchasing decision it is important to identify the light source you are viewing the stone and to view the stone in as many lighting environments as can be found. Regardless of my geographic location at the time, I always compare each stone in daylight and 3200K incandescent to see how the stone reacts at both ends of the lighting spectrum.

If a consistent workable colored stone evaluation system is ever created, the lighting environment will of necessity be standardized. To achieve reproducible results, there are three variables; the observer, the gem observed and the lighting environment. The standardization of the lighting environment will remove one variable. This leaves one remaining variable, the observer. Either we must accept some nuances of subjectivity or build a gem grading robot replace to connoisseur’s eye and dictate our taste.

Coming To R. W. Wise, Goldsmiths. Saturday, November 10th

Leave a reply

Coming to R. W. Wise, Goldsmiths:

By Appointment: Private Show:

Friday Afternoon November 9^th and Saturday, November 10^th

Fine Black & Boulder Opals direct from the land downunder.

The holidays are fast approaching and we are gearing up. Our favorite opal dealer Damien Cody aka “The blunder from downunder” will be visiting us on Saturday, November 10^th.

Damien has hands down one of the finest inventories of black and boulder opal in the world. His company has been buying directly at the opal fields of Lightning Ridge for over 20 years.

If you are interested in a fine black or boulder opal at a direct from the fields price please give me a call. 800.773.0249(413.637.1589) We will be more than pleased to set up a private appointment for you to view these wonderful gems. Mr. Cody has opal in all price categories. Be prepared for a visual feast! Our goldsmiths will be standing by for your Xmas order.

Mark Your Calendar:

In our Lenox gallery; Saturday December 23rd (all day). Steven Webster Trunk Show. See the latest designs from the award winning British designer Stephen Webster just in time fore the holidays. For a preview of Stephen’s magnicent jewels, visit Stephen’s website www.stephenwebster.com

Light Up Your Life; Lighting and Grading Gemstones, Part I

1 Reply

LIGHT UP YOUR LIFE

Lighting and Grading Gemstones Part I

©2006

Richard W. Wise, G.G.

It used to be so simple, the brighter the light the better the light. You had the light from a fire and the light from the sun, that was it. In those good old days it was easy to figure out watt was watt! Today we have a myriad of options, “warm light”, “cool light”, “daylight.” Gem dealers are beginning to discover that the lights that make his rubies look like a pigeon’s blood may make his tourmaline look like a dog’s poop. As for the buyer, caveat emptor baby, check the bulb!

We are all familiar with the daylight standard: diamonds and colored gemstones are supposed to be judged in north daylight. Why?, because north daylight, specifically north daylight at noon is white light balanced between the red and blue spectrum. Sounds simple, but wait a moment! Dealers have long realized that the quality of daylight differs in locations throughout the world. North daylight at noon in Bangkok is qualitatively different from north daylight in New York.

The quality of natural daylight is affected by several factors, including latitude and air quality. In addition, the relative strength and color composition of daylight changes as the day progresses. “Don’t buy blue sapphire after 2:00pm“. That was the advice my Bangkok broker gave me on my first trip to Thailand. This dealer’s truism teaches a basic fact that as the day progresses the color composition of sunlight moves from yellowish into the blue range then toward red at sundown.

Color scientists measure color as a function of light temperature and express it in units called Kelvin (K). a light filament heated red will have a Kelvin temperature of 1000-1500K, orange like a candle flame has a color temperature of 1500-2500K, yellow between 2500-4000K, white as in daylight is defined as a range; 4000-10,000K. In practice, increasing Kelvin temperature reduces yellow and adds blue.

If we wish to get a true color rendering using the daylight standard we will want a bulb that produces average noon sunlight with its relatively balanced color spectrum with a color temperature between 5500-6500 Kelvin. Unfortunately, the Kelvin temperature of an incandescent lamp falls between 3000-3200. The new low-volt quartz halogens have a color temperature of only about 3200K. Light in this temperature range is distinctly yellowish and will enhance the look of stones in the yellow, orange and red range. It will add an attractive bluish hue to chromium-vanadium colored gemstones like emerald, chrome tourmaline and tsavorite garnet. However, some Emerald, particularly Zambian emerald, can look distinctly overblue in this type lighting and 3000k light tends to muddy the crystal (reduce the transparency) of iron colored green and blue stones such as tourmaline and sapphire.

Daylight equivalent lighting does exist in fluorescents but not in incandescent single point spot and flood lighting that is used by most dealers and jewelers to bring out the brilliance of a gemstone. Daylight fluorescent bulbs with Kelvin temperatures between 5500-6500 are available. These lamps are marketed, usually as “daylight” lighting by several companies under various trade names. Unfortunately fluorescent lamps generate a diffused light and produce insufficient punch, what scientists call lumens, to bring out the best sparkle in your gems. To further complicate matters, there is no recognized international standard for a daylight bulb. Each manufacturer decides for himself what to consider “daylight”.

Coming next: Part Two, Learn what types of lighting the experts favor, Stay tuned…

So, you want to learn more about lighting and judging gemstones? Read the book:

“Secrets Of The Gem Trade is very highly recommended to anyone interested in gemology as a superbly organized, authoritative, comprehensive, and easy-to-follow reference.”
Midwest Book Review
April 2006

www.secretsofthegemtrade.com

Mozambique Cuprian Tourmaline, Part III

2 Replies

Mozambique Cuprian Tourmaline, Part III

Purple Cuprian; A dilemma:

By Richard W. Wise, G.G.

“I know what you’re thinking. Did he fire six shots or only five? Well, to tell you the truth, in all this excitement, I’ve kinda lost track myself. But being as this is a .44 Magnum, the most powerful handgun in the world, and would blow your head clean off, you’ve got to ask yourself one question: Do I feel lucky? Well, do ya punk?”

Clint Eastwood

As tourmaline aficianados know, there are few truly rare colors of tourmaline. A pure yellow without a stong green secondary hue is quite rare and I have never seen a true violet but until recently, purple was the one spectral color that absolutely did not exist in tourmaline. Yes we had purplish reds but until last year when the Alta Lighona tourmalines from Mozambique entered the market, never a stone with a purple primary hue. (pictured above: 15.5 carat purple Mozambique cuprian tourmaline courtesy Pala International)

In early 1989 when the first curpian tourmalines from Paraiba appeared in the market in Brazil some were sold unheated. Most of these stones were a dark toned greenish “sapphire” blue, a “Thai sapphire blue” to be precise. In those days, blue was the most expensive, elusive and sought after color in tourmaline. Rumors whispered of a pure blue gem that was reputed to rival the finest in Burmese sapphire. This was the holy grail of tourmaline. I recall holding on to one parcel of natural dark blue Pariaba for several years before I burned them just in case the demand for the medium electric blue proved to be a passing fancy. Well, as we know it did not and when I finally did heat it, the result was a half dozen pure medium toned visually pure Carrribean blue gems that I sold at a substantial profit.

Since that time I have seen many examples of blue tourmaline including the famous Manoel Mutuca (described by Proctor as “sapphire blue” see Gems & Gemology, Spring 1985, p.11)) and Santa Rosa material but none (at least so far) with a true pure blue hue. Blue tourmaline always has a distinct greenish secondary hue which becomes quite evident when it is compared stone to stone with fine sapphire. Blue tourmaline can be exceptionally beautiful but it looks like tourmaline not sapphire.

To burn or not to burn or “Do I feel lucky? Well, do ya punk?”

With the entry of Mozambique curprian tourmaline we have a dilemma similar to the situation with the early Brazilian curprian tourmaline namely that some of the unburned material has a rich pure purple hue that reminds one of Siberian amethyst or fine purple sapphire. The difference is that unlike the rather dull greenish blue unheated Paraiba, this stuff is beautiful,

The Mozambique purples have a hue that is rich and pure. So, to burn or not to burn, that is the question, according to both Gene Flanigan from Precision Gems and Josh Hall at Pala International, these deep purples are also the best candidates for the oven, they heat to a neon pure medium “Paraiba” blue.

Some dealers have chosen the obvious solution. If you want a pure purple but burnable stone they will charge the same price as for the neon blue.(pictured above: unheated cuprian rough from Mozambique). Pictured below is an exceptional 1.89 carat custom cut Carribean blue cuprian stone cut from the center piece of rough. After and before; the first image shows the cut stone before heating. The second image shows the stone after the heating process was completed. The stone, currently available for sale at www.rwwise.
com was cut by Gene Flanigan a very talented lapidary artist from upstate New York. (Images courtesy Gene Flanigan: www.precisiongem.com)

Will purple tourmaline go the way of fine star sapphires that hardly exist anymore because they can be burned and faceted? I don’t think so, some of the fine purples simply possess problematic inclusions that make them risky candidates for burning. I found an 8.19 carat oval, a lovely example of Mozambique purple on my last trip to Asia. This stone faces up clean but under magnification shows long growth tube inclusions and cannot be burned. It is out having its picture taken and will be posted in a later blog. Logically purple cuprian tourmaline will have a two track price structure. Stones with a high degree of clarity under the loupe will sell for prices that may be double that for stones with certain types of inclusions whether visible or not.

Bits and Pieces:

I get lots of emails. Don’t think I’m not grateful. Every once in a while a real interesting one comes through the mailbox. take this on:

Position Available:

Dear Mr Wise,

We are Stargate, diamond trading division of Ebenhaezer Bank Consulting Group of Belgium, operating in thirty countries worldwide. We have read your blog regarding the appraisal of stones by qualified experts. We have constant need of qualified gemologists, expert in assessing ROUGH DIAMONDS, and have great difficulty identifying where they can be located.

We offer good working conditions, contracts, and a fair remuneration.

A special need has arisen in Bangui, Central African Republic, where we are currently (this week) accepting a large consignment. We require the services of a qualified gemologist, expert in rough diamonds, to assist our team there.

Would you be kind enough to assist us at your earliest convenience?

Yours sincerely,

Lucilla Arioti

Global Client Relationship Manager, EMEA

Stargate,

a division of Ebenhaezer Bank Consulting Group

Telephone: London +44 207 870 5389

I am not familiar with Stargate but believe the lady is serious. She even called and left a message on my machine. So if you are a gemologist in search of adventure give Lucilla a jingle. This time next month you could looking at sparklies and sipping pina colodas in beautiful downtown Bengui. As for myself I’d love to go along but I can’t give up my day job but when you get there be sure to drop me a line and oh do be sure to take along a flack jacket.

New Site with excellent online library of inclusions:

Got an email from a French gemologist: Marie-France Boursier-Brard. Ms Boursier-Brard has developed an excellent site with online images of inclusions. The site is quite comprehensive and well organized. Just click on: www.gemmes-inclusions.com

Check out my book Secrets of The Gem Trade; The Connoisseurs guide To Precious Gemstones: www.secretsofthegemtrade.com.

Now at 30% off just $27.95

“This book takes a much-needed sledgehammer to the industry’s conventional wisdom about what makes a gemstone precious, and in the process builds a solid foundation for anyone who wants to understand the true beauty and value of gemstones.”

Morgan Beard
Editor-in-Chief Colored Stone Magazine

Getting an Appraisal; Part II; The games jewelers play

Leave a reply

by Richard W. Wise, G.G.

Jewelers sometimes use appraisals as sales documents. “I’ll sell it to you for $1,000.00 but I’ll give you an appraisal for $5,000.00.” The IRS defines value as what the willing buyer pays the willing seller. In this case we know the seller is more than willing and to entice the buyer he provides an appraisal document that inflates the value of the item sold. The replacement value is the price the buyer paid. It is difficult to believe that anyone would fall for this but they do. Not only is this practice unethical but over the long run the buyer pays through the nose.

Insurance premiums are based upon the replacement price stated in the appraisal document. Insurance companies are well aware of the practice of inflating value, a practice they could eliminate it with the stroke of a pen. They purposely choose not to do so. In fact they are more than willing participants in a defacto fraud that makes them huge profits.

Most insurance policies contain a clause that allows the company to replace a lost item with “like kind and quality.” Insurance companies maintain ongoing relationships with certain jewelers and manufacturers that allow them to buy at wholesale. You insure at retail, they replace at wholesale or in the case of the example sited above they collect a premium based on five times the retail price year after year and if a claim is filed they replace at their cost which may be a fraction of the insured value.

I have personally seen instances where insurance companies will try to replace fine handmade originals with generic pieces of production jewelry. In one instance one of our clients lost a one of a kind handmade ring set with a rare fine quality Malaya garnet. It was only the client’s stubborn refusal and willingness to sue coupled with the fact that I had written an article on this garnet that prevented the insurance company from trying to force the client to except a cheesy commercial substitute worth less than ten percent of the original. The company’s position was that a ring is a ring and one is much like another. That’s like saying that a painting is a painting and a Picasso might be legitimately replaced with Elvis on velvet.

Not all insurance companies engage in this sleazy slight of hand. I have worked with Chubb and it is one example of a company that will pay the full insured value when an item is lost with no questions asked. My understanding is that Chubb charges higher premium but you get what you pay for.

There are obviously some cases where the replacement cost will be higher than the selling price. The obvious example is an appraisal done years after the purchase. Another example is the ruby sighted in the previous post. After my trip to Hong Kong it was obvious that I could not replace that stone for the price the client paid. In these sorts of cases both should be included in the appraisal and then it is up to the client, in consultation with the insurance company to decide what level of risk he or she is willing to assume.

READ ON; Secrets Of The Gem Trade is now 30% off for a limited time. All the secrets for only $27.95. Read a sample chapter or ORDER NOW: www.secretsofthegemtrade.com

Getting an Appraisal; Some Do’s and Don’ts

2 Replies

Gems: Grading the Crème de la Crème, Part IV

By Richard W. Wise, G.G.

In the last three posts on this subject I discussed some of the rare characteristics that make certain gemstones so valuable. Value is naturally of great interest to the gem connoisseur/collector. How does a collector determine if he is paying the right price? In other words how does one go about establishing the value of one of a kind, ultra-fine gems?

First let’s establish what you don’t do. Don’t take the stone to your local jeweler even if he is a graduate gemologist unless he stocks comparable qualities of the gem in question. Most local jewelers know colorless diamonds but few have a working knowledge of colored gemstones. As with any sort of appraisal, the prospective appraiser should have a thorough day-to-day familiarity with the gem to be appraised.

Familiarity is easy enough to establish. If ruby is the gem at issue, go to the jeweler and ask to see his rubies. If he stutters and stammers and suggests he can have anything you want in the store in a matter of days, move on. If he doesn’t stock the stone, he doesn’t know the stone.

Watch out for the low-ball…

If the potential appraiser’s first statement, after you show him the gem and tell him what you paid is, “you paid way to much for that stone.” Run like hell! Why, because I guarantee that the next words out of his mouth will be: “I could have gotten you a similar stone much cheaper.” These are not statements made by a disinterested professional they are what they sound like, the words of a jealous competitor. The practice is so common it even has a name; low-balling. Some jewelers low-ball because they believe if they can discredit the competition, they will get the business. What actually happens is that the client becomes distrustful and the whole profession is discredited. If a low-ball raises a question in your mind; call the person’s bluff: “Ok, show me a better one, cheaper!.” Usually that will end it. Recently a client of mine went one better, he asked to be shown a comparable stone and agreed to buy it if the dealer came up with one. He still has my stone and is yet to see a match.

The next possibility is a professional appraiser. Over the past two decades gem and jewelry appraisal has become professionalized. There are three major appraisal organizations: The National Association of Jewelry Appraisers (NAJA) http://najaappraisers.com/ , The International Society of Appraisers (NSA) http://isa-appraisers.org/ and The American Society of Appraisers (ASA): http://appraisers.org/. These organizations have standards of education and codes of ethics to protect the client. In addition they use methodologies that provide some assurance of accuracy. However, I think the same standard applies. Does the appraiser have experience with the gem in question?

How often have I been asked for a: “Just off the top of your head, I won’t hold you to it” appraisal? An appraisal is worth what you pay for it. A good appraisal takes time and time is money. Jewelers who give out this sort of verbal appraisal are doing neither their client nor their profession any good. Courts in some jurisdictions have held that a free appraisal is worth just what you paid for it…nothing! And, by the way if you are a professional you may be “held to it” in a court of law. Jewelers are not the only ones who do this sort of thing, professionals do not always act professionally. May I offer a cautionary tale?

Take me out to the ballpark…

About two months ago I sold an extraordinary 3.30 carat Burma Ruby (pictured) The client, rightly concerned with value, wanted the gem appraised. He asked me if I could recommend and appraiser and aside from the ethical problem of the seller making such a recommendation I had a tough time thinking of anyone other than a wholesale dealer specializing in rubies with experience enough to do it and wholesalers do not know the retail market. To aid the client I obtained an American Gemological Laboratory full quality report. The AGL report graded all aspects of the gem and issued an overall quality grade. I highly recommend this report for important gems. It provides one objective basis to begin the valuing process. (see the report at www.rwwise.com, click gallery, gemstones, ruby)

The client then contacted a professional member of one of the organizations listed above and asked the appraiser for a ballpark estimate and faxed the AGL report to the appraiser. Without ever seeing the gemstone, this appraiser gave the client a “ballpark” price that was so ridiculously low that the client, who had been looking for a ruby for several months realized the price was absurd and decided he needed another appraiser.

How could any professional appraise a gemstone without examining it? You’ve got me! In the case of this so-called professional, he hit a foul ball. Luckily, the client knew more than the appraiser otherwise I might have lost the sale.

The client then asked two well known gemologists, Richard Drucker and Stuart Robertson of Gem World International publisher of The Guide, a wholesale gemstone price guide, to do an appraisal. In a subsequent article in Gem Market News written on appraising this ruby here is what Mssrs. Drucker and Robertson said this stone:

“Pricing this ruby was a challenge…The color was at the top of the spectrum…”

“we looked for comparables…Rubies of this caliber cannot be priced by the cost method and only market data will suffice…”

“…This becomes a gem for the collector’s category and that is an important lesson in pricing. The stone is an example of a gem that grades above The Guide’s extra fine category.”

Gem Market News, Vol. 25, No. 5, September, October 2006, p. 12

Evaluating an ultra-fine gem is difficult because, as Drucker says, you must find comparable stones and if you can’t find comparables you are like a tight rope walker dressed in his underwear balanced on a high wire working without a net. In the end, Drucker & Robertson, after consulting a number of dealers, appraised the stone for substantially more than the client paid and several times the price suggested by Mr.ballpark the professional appraiser.

To sum up, if you want a gem, any gem, appraised. Find a professional with demonstrated familiarity with the gemstone. Check the credentials of local jewelers by checking what they have in their inventory. If they don’t stock the stone, they don’t know the stone. Choose a disinterested professional and pay the price. Don’t expect something for nothing, get a signed document and watch out for foul balls and low inside drives.

Interested in reading more about real life adventures and secrets of the gem trade? Follow me on gem buying adventures in the exotic entrepots of Burma and East Africa. Visit the gem fields of Austrailia and Brazil’s famous Capao mine. 120 photographs including some of the world’s most famous gems. Consider my book: Secrets Of The Gem Trade, The Connoisseur’s Guide To Precious Gemstones.

“Wise is a renowned author… He’s
done a marvelous job of this first book, monumental work, a tour de force…My recommendation: Buy this book”.

Charles Lewton-Brain, Orchid

Only $39.95. You can read a couple of chapters online: www.secretsofthegemtrade.com.

Buy it on Amazon: www.amazon.com

Ruby & Sapphire; Prices at the Hong Kong Show

Leave a reply

Ruby Prices Way Up at Hong Kong

By Richard W. Wise, G.G.

Dateline: Hong Kong:

In the latest issue, The Guide’s Gem Market News announced 2006 price increases in natural unenhanced ruby and sapphire in the extra fine grade at between 50-100%. This follows a 35-100% increase in 2004. The Guide is a trusted industry resource with price grids for most colored gemstones as well as diamonds. Gem Market News is The Guide’s quarterly newsletter. (pictured above: 7794, 1.84 carat heat enhanced “pigeon blood” Burma ruby from our collection)

If the Hong Kong show is any indication this analysis, in ruby at least, is not far off. The strongest increases are in larger stones. This means ruby over 2 carats and sapphire in the 5+ carat range.

Hong Kong is a good place to get a feel for price increases. Many Asian as well as high end European dealers setup in Hong Kong. (Pictured right: 7249, 1.74 cart rectangular cushion, natural Ceylon sapphire with Kashmir like color from our collection)

Ruby prices for both natural and heated stones have shown marked price increases across the board with very little in the ultra-fine category available at any price. Sapphire price increases are a bit spotty and judging from what I saw on offer, more modest than The Guide suggests with some bargains still available. That said, I saw little in natural sapphire from any location to crow about. Almost nothing was available in Hong Kong in world class or connoisseur/collector quality. Fine natural Burma sapphire hardly exists. Even among heated stones there was not much of note. (Pictured left: 7133, Natural round 1.35 carat Burma sapphire from our collection)

Some of the huge ruby price increasing may be the result of strong auction prices. Two rubies in the 8+ carat range sold between 2-3 million at auction in the last three years. This coupled with the fact that the “new” ruby mines at Mong Hsu, the main source for heated ruby, are producing very little above 1.5 carats makes for a much reduced supply.

Overall business at the show was off. From those dealers I spoke with it was clear that 2006 may not be a banner year for the gem trade.

Understand ruby and sapphire from the ground up:

“whether you like to know what the best colour is in Tanzanite, or how to grade a Diamond, you will find it in this book. No other book I read before dealt with this topic is such detail as Richard Wise’s masterpiece

A. Van Acker, FGA
Amazon June 2005

Read a free chapter: www.secretsofthegemtrade.com

Mozambique Cuprian Tourmaline: Part II; Beyond the hype

Leave a reply

Dateline: Hong Kong

Arrived in Hong Kong Monday night locked, loaded and ready to expose this Mozambique Cuprian tourmaline for the over-hyped fraud I thought it was and got a surprise. Quick answer to the burning question of the day; yes, there are some Mozambique stones that will stand up to the finest from Brazil.

Recently I have seen quite a bit of the stuff and found some of the asking prices bordered on the ridiculous. Examined one 7+ carat green tourmaline that looked like, well a medium dark yellowish green tourmaline, nothing special but the price. If it had been offered to me for $100 per carat I would have sent it back but it was Cuprian so the wholesale asking price was $3,500 per carat. (see part I, super star stone or overripe hype)

A lot of the Mozambique material out there simply does not make the grade. Yes you can find Caribbean aka neon-blue, aka windex-blue that is, a visually pure light/medium toned blue that is of the same hue as Paraiba but read the book www.secretsofthegemtrade.com; color divides into hue, saturation and tone with Paraiba and all its wannabes it is all about the saturation baby. Much of this material has a subtle gray mask, so subtle that you can’t actually see the gray; you just get the impression of cool and dull. This can be difficult to detect because blue is, generally speaking, a cool color. For collectors who depend upon laboratory reports rather than their eye to make a buying decision that can be particularly vexing but “buying the cert” has always been a snare and a delusion. So, if you need a certificate to tell you whether the stone is beautiful I suggest a new hobby.

How good is the best Mozambique compared to the Paraiba paradigm? On a scale of 1-10, the best of the Mozambique achieves a solid 8.5-9.0. I saw two stones that were 9+. So, is Mozambique over priced? The best, definately not but the common sort of pale material with current asking prices of several thousand dollars a carat is best avoided. Those who hope to ride on the coattails of a legend will be disapointed. Stones of this description are destined to fall from four figures to three.

Judging by Hong Kong, the price structure for very fine Mozambique Cuprian tourmaline is very much in place with little variation from dealer to dealer but overall the prices are half or less than you would expect to pay for comparable Brazilian gems.

Coming Up:

Big Price Increases in Fine quality untreated ruby and sapphire, are they for real?

Some experts are claiming 100% price increases in untreated fine quality ruby and sapphire. What’s the word from the Hong Kong Show? Stay tuned.

Choosing The Perfect Pearl

Leave a reply

Ten, make that eleven tips to help you choose the perfect pearl

by Richard W. Wise, G.G.

1. There are two types of pearl, natural and cultured. In today’s market just about every pearl you see will be cultured meaning that the hand of man had something to do with the creation of the pearl. (pictured above a necklace of mixed South Seas white and golden pearls)

2. We are experiencing a pearl Renaissance. There are more types of pearls on the market today than ever before. Twenty years ago the Japanese Akoya stood virtually alone. Today you can choose from: Freshwater pearls, South Seas white, Tahitian black and South Seas golden pearls.

3. What’s the best buy in pearls? Probably the Chinese Freshwater, (pictured left 8.5mm round natural color Chinese f/w pearls) There are two ways to create a cultured pearl, bead nucleation and tissue activation. Pearls that are bead nucleated have a large bead made from shell and thin covering of nacre depending upon how long they are left in the mollusk. Chinese freshwater pearls are tissue activated, have no bead and are pure pearl. They are available in natural pastel or white and in their finest qualities have some of the characteristics of natural pearls. Be careful, over 90% of Chinese freshwater pearls are of marginal quality. The best will stand toe to toe with any pearl in the world and can be purchased for a third of the price. To help you in selection, pay careful attention to the following guidelines:

4. Pearls are often treated, usually to change or improve the color. Pearls are routinely dyed and irradiated. Natural colors are, by far, the most beautiful. Japanese Akoya, the pearl that is seen most in the market is routinely bleached white then dyed to give it a pinkish overtone. If the color looks too good to be true it probably isn’t.

5. A fine pearl has what experts call “life”. This is a combination of high surface luster and overtone and occasionally orient. All pearls exhibit luster, those with thick nacre will usually show excellent luster. Observe the pearl(s) on a white background under a light bulb, if you can distinctly see the outline of the bulb the pearl has high luster.

6. Some pearls exhibit an ephemeral misty glow that seems to hover over the surface of the pearl. This is called overtone. Not all pearls exhibit overtone, for example, it is very rare in South Sea white pearls. If present in white pearls, the overtone is usually pink, in Tahitian black pearls, green, red or blue or some combination (pictured right). Orient is rare in round and semi-round cultured pearls. Orient may be defined as a rainbow affect that changes as the pearl is rotated in the light. Orient is chromatic, meaning it will show all the colors of the spectrum whereas overtone is normally monochromatic exhibiting one color such as pink. A ball bearing can have wonderful luster but the addition of overtone or orient adds dimensionality and life to the pearl (pictured right: orient in Chinese f/w baroque pearls. Below (right) distinct orient in a pearl shell).

7. To judge if all the pearls in a strand are round, hold the strand taught between your hands and rotate the strand between your fingers. In a round strand you should see no movement but if some of the pearls jump about like the cams on a cam shaft, the strand is not completely round.

8. Odd shaped pearls, called baroques, are not to be disparaged. If they have good luster, no scratches or cracks they have a younger hipper look than the more expensive rounds. You can wear them with jeans and they are available at a substantially lower price.

9. Pearls have flaws just like other gem. These may be dimples, scratches or cracks. A dimple here or there should not be of much concern however, one that looks like it has a bad case of chicken pox should be highly discounted. A pearl with a deep scratch or crack is unacceptable.

10. Beware lower priced Japanese Akoya pearl, if your grandmother has a strand of white round pearls they are likely Akoya. These are formed by placing a shell bead in the oyster. In the last few years, Japanese farmers have dramatically reduced the time the pearl is allowed to develop in the shell resulting in pearls that are little more than nacre plated beads with less than ¼ millimeter of pearl essence or nacre over the shell bead. These pearls are often bleached then dyed pink to simulate overtone. These pearls lack luster and are prone to flaking.

11. Pearls come in many nuances of color but color is not the issue. It doesn’t matter how good the pearls look in the jeweler’s case, the real question is how the pearl looks against your (the wearers) skin. Pearls come alive when placed against skin of an appropriate color and texture. This is a characteristic I dubbed simpatico in my book: Secrets Of The Gem Trade, The Connoisseur’s Guide To Precious Gemstones. Don’t prejudge, test the simpatico of each strand by placing it against the skin on the inside of the wrist. The skin in this area is the same color and texture as the skin around the ears and neck. The result may surprise you.

Need more information on pearls?

Follow me on gem buying adventures in the pearl farms of Tahiti. Visit the gem fields of Australia and Brazil. 120 carefully selected photographs showing examples of the highest quality gems to educate the eye, including the Rockefeller Sapphire and many more of the world’s most famous gems. Consider my book: Secrets Of The Gem Trade, The Connoisseur’s Guide To Precious Gemstones.

“Wise is a renowned author… He’s
done a marvelous job of this first book, monumental work, a tour de force…My recommendation: Buy this book”.

Charles Lewton-Brain, Orchid

whether you like to know what the best colour is in Tanzanite, or how to grade a Diamond, you will find it in this book. No other book I read before dealt with this topic is such detail as Richard Wise’s masterpiece.”

A. Van Acker, FGA
Amazon June 2005

“Secrets Of The Gem Trade: The Connoisseurs Guide To Precious Gemstones by Richard W. Wise is an impressive new reference for dedicated dealers and collectors of gems, gemstones, and … pearls. Introducing and descriptively exploring each and every gem covered in the easy-to-use reference, Secrets Of The Gem Trade contains an illustrated summary of each stone inclusive of its history and general information, hue and tone, saturation, which may be noticed as the finest, an understanding of the particular gems rarity, and the caution for synthetics and how to depict them, however depending upon the stone there may be description of clarity, color fading, multi-color effect, etc. Secrets Of The Gem Trade is very highly recommended to anyone interested in gemology as a superbly organized, authoritative, comprehensive, and easy-to-follow reference.”

Midwest Book Review
April 2006

Only $37.95. Read a couple of chapters online: www.secretsofthegemtrade.com.

Buy it on Amazon: www.amazon.com

Labels: Al Gilbertson book, american cut, Gemological Institute of America, GIA diamond certificates, grading, ideal cut, The First 100 years, tolkowsky cut

posted by Richard W. Wise @ 12:16 PM