Every year for Christmas, we jewelers put our best foot forward, looking to make special pieces that will find their way into Santa’s sleigh. This year, I was able to find some spare hours to make these three special rings that feature one of the world’s most unique gemstones, the American Fire Agate.

This 21.20 ct beauty features a wonderful dome of bright red wreathed with green– a touch of purple peeks out occasionally. I hand carved the wax model to fit the stone perfectly, then cast the piece in 14k yellow Harmony gold. Jeweler Scott Reeves actually has to hammer the gold around the gem to accomplish my proprietary setting style.

This large man’s ring is dramatic and striking, measuring about 21 x 19 mm across the top. The stone came from Bob Beaudry, a major collector of finest fire agates — he says the source was Slaughter Mountain, San Carlos Reservation, Arizona.  Happily, it’s already found it’s way to a new home!

The Fire Agate is a rare cryptocrystalline form of the earth’s most common mineral, quartz, found only in Arizona, California, New Mexico and Mexico. Gemmy stones like these are actually carved to expose the iridescent spectrum colors. The color layers are thinner than a breath of air on a window pane, and they follow the distinctive bubble-like botryoidal forms that characterize this gem material, so the carver must patiently and carefully take away just enough material to bring forth the glowing colors.

For the ladies, I created these two 14k yellow gold rings, one with a crimson twin, one with a holly green gem. Both stones are probably also from the Slaughter Mountain locale, and were cut by Ryszard Krukowski, Fire Agate Studio.

These rings are truly one-of-a-kind original designs, just right for the person who appreciates fine quality unique American gems and hand crafts. We have more great stones in inventory and will be glad to carve a ring just for you. Now Showing at Mard

1.24 ct. Ruby Engagement Ring

Celebrity brides are becoming known by their engagement ring choices, and the colored gemstone ring is very much in the limelight. Princess Kate, in the wedding of the decade, wore “The Ring“, her famous heirloom sapphire and diamond ring, Penelope Cruz is setting style with her sapphire and diamond ring, and Jessica Simpson is stunning in her gorgeous ruby and diamond ring.

There is no question that the colored gem engagement ring makes a statement of style and individuality, but there are other compelling reasons to make this your choice, including beauty, rarity, durability, and of course, affordability.

Compared to diamond, a truly beautiful colored center stone is well within reach of most couples. This wonderful 1.24 ct. natural unheated ruby appears in size like a one carat diamond, yet its price is much less than half that of the diamond.  The price of a better (not best) quality GIA certified one carat round diamond, say SI1 H color, is about $7000 just for the diamond.  The total price of our 14K ring including 1.24 ct. ruby, and .39 ct VS-SI near colorless diamonds, $2450!

1.34 ct. Blue Sapphire

How about this ring centered around a bright blue sapphire from Tanzania, set in 14k white gold with diamonds for only $2750?

2.11 Ct. Pink Sapphire

Our lovely hot pink sapphire from Sri Lanka, in the popular cushion cut, also just $2750!

All sapphires and ruby and many other gems are super durable and will provide a lifetime of sparkle and color.

.70 ct. natural Alexandrite

A more unusual choice, this exotic natural alexandrite, famous for its color change, will flash reddish purple in candlelight, blue green in daylight. This ultra rare gem of fine quality set in 18k white gold with diamonds is $5495, still much less than our one carat example

2.74 ct. Spessartine Garnet

For a really unique look, this bright spessartine garnet from Africa is oh so different, simply dazzling and passionate in its color. In 14k white gold, haloed with .46 ct. of diamonds, for just $2250!

You can tour our Gallery of Gems to see a rainbow of gemstones perfect for the engagement ring– for cool green, a fabulous emerald,  I-16148, sizzling red, a rich natural spinel, I-15227, sunset pink, a rare padparadsha sapphire, I-9149, or royal purple,  a fancy sapphire from Madagascar, I-488. All are premium heirloom quality gems, yet all are priced less than our one carat diamond example.

In addition to the Gallery, you can take advantage of our professional gem brokering service. We’ll search the gem world to provide you with exactly what you want at great savings over normal retail prices.

Our professional gemologists will be happy to advise and help you select a gem you’ll love and that will surprise and delight you and your friends and family. We’re open Tuesday thru Saturday, 10 am to 5:30 pm.  You can call us at (951) 682-2325 or contact us at customerservice@mardonjewelers.com

Want to own a piece of historical art jewelry? We are pleased to showcase this wonderful handmade Modernist brooch/pendant of 18k yellow gold set with diamonds and a fabulous red fantasy cut tourmaline weighing 10.05 carats, created by the brilliant lapidary artist, Bernd Munsteiner.

Classically trained in Pforzheim and working in Idar Oberstein, Munsteiner became famous in the gem world during the 1970′s for his innovative gem cutting. His stated mission- “I try to show in my stones how human life is reflected in the structure of minerals.”

Using high quality gem materials, he pioneered wonderful abstract sculptures, true works of art characterized by unusual shapes highlighted with reverse facets and grooves carved into the flat planes of the gem, creating unique reflective patterns never before seen in gemstones. He also became known for focusing on gem inclusions in his compositions. His award winning work opened the door on a whole new field of lapidary art where artists like Wallace Chan could explore entirely new ways to work with inclusions and light within transparent gems.

His family continues his work to this day. Among other awards, Mr. Munsteiner received the coveted Life Honorary Member Award from the American Gem Trade Association in recognition for his lasting contributions to the time honored field of the Lapidary Arts.

Master goldsmith Patrick Irla crafted this classic example of Modernism around Munsteiner’s great tourmaline. From the provenance provided by the original owner, we know the stone was cut prior to 1987 and the brooch created prior to 1989.

If you would like to acquire this work of art, inquire at 951 682-2325 or email jim@mardonjewelers.com

1.97 ct Irradiated Diamond, Fancy Vivid Yellow

We just appraised this beautiful bright yellow ~2 ct. round diamond for a client. She had inherited the stone, which was accompanied by an appraisal from a gemologist which described it as a “Canary Yellow” diamond, which implied but didn’t state specifically that the stone was natural-color. Our client said the diamond had originally been purchased at an estate sale for $1200, but this appraisal was for $43,000!

The antennae immediately went up!  First, it’s very unusual to find round natural-color yellow diamonds of this size, especially in today’s market. Diamond cutters have discovered that the Radiant cut maximizes the intensity of color in yellow diamonds, so most of the large natural-color yellow diamonds you see nowadays are radiant cuts.

The clarity of the diamond was at least VS1, perhaps better.

And the color– very intense for a natural-color yellow and thus very rare.

The combination of round shape, high clarity, and bright yellow color meant that if the stone were natural-color,  its appraised value would be well over $70,000! Our advice was to remove the stone from its mounting and send it to GIA for a full grading report to determine origin of color.

As we suspected, the stone proved to be artificially irradiated, with the color grade described as Fancy Vivid Yellow, Artificially Irradiated. Still a very valuable diamond, appraising well over $12,000 for replacement by insurance, but not nearly as rare and exotic as a round VVS2 Fancy Vivid Yellow diamond, natural-color– that would be worthy of an Important Jewels Auction at Christy’s or Sotheby’s!

For an interesting look at some very large and valuable natural-color rough diamonds, including several levels of Fancy Yellow,  follow this link– http://www.rockwelldiamonds.com/i/rcw/DiamondGallery.swf

Commentary– the use of the term Fancy has evolved over the years. The original designation “Fancy” was used for diamonds of natural color only, which distinguished them from diamonds of treated color.  The level and quality of the color would be described and graded with the terms following “Fancy,” such as Fancy Light Yellow or Fancy Intense Greenish Yellow, etc.

The GIA management and board made a major change in this practice about 10 years ago, after HPHT treated diamonds began showing up in the labs in significant numbers. HPHT means High Pressure High Temperature, a hi-tech treatment developed in the 1990′s that is applied to brownish type 11a diamonds to improve their color grade. Some of these stones were grading near colorless, even colorless, as high as D, while others changed to a range of colors including pink, blue, or yellow! The problem was that some of these HPHT treated diamonds were sold and fully disclosed as being treated, while others were not.

Eventually, the decision was made for the GIA Gem Trade Labs to color grade HPHT treated diamonds (and issue GTL reports with the grading), so long as the girdle of the diamond was laser inscribed HPHT, and further, to grade the color of artificially irradiated diamonds so long as the girdle is laser inscribed “IRRADIATED”– and GIA took it on themselves to laser inscribe any treated stones that came thru their labs.

So now, we have a diamond market in which the color of both natural color and artificially treated diamonds is graded as Fancy. We are not fans of this practice– to us, it dilutes the color grading of the ultra rare natural-color diamonds, and it makes the distinction between natural-color and artificially treated colored diamonds less clear to the consumer.

While GIA is indeed inscribing the girdle of the treated diamonds it sees, the inscription can be can be very hard to see and easily overlooked.  Also, the inscription can be removed by polishing or faceting the girdle of the diamond. We shot this image of the laser inscription on our diamond with a high quality 100mm macro closeup lens– judge for yourself how noticeable the inscription is.

Royal Ring by Mardon

We’ve just completed this gorgeous sapphire and diamond ring, inspired by the engagement ring of Lady Diana and soon-to-be Lady Kate. This basic design, where a colored gemstone is surrounded by a circlet of diamonds, has been a favorite for centuries. Since everybody and their uncle has been doing versions of the ring, we might as well show off a well made quality piece by Mardon.

We studied the available photos of Lady Diana and Kate Middleton wearing the ring because we wanted to portray the Lady Di design as accurately as possible and get the exact structure and prong layout. It was challenging to keep the overall proportion and look of our ring similar, because we used a smaller sapphire– 3 ct vs the original 12. And where her stone is an oval, ours is similar but slightly different–the classic cushion antique shape often used for fine sapphires. Adjusting the stone sizes for the cluster surrounding the center, we were able get the same number of diamonds. We used a good match of VS quality diamonds, all recycled from estate jewelry!

You can see the gem report for the sapphire in our Gallery of Gems, I-17700. It’s a classic cushion shape, beautifully cut, eye clean, with a vivid velvety medium dark blue color. Although a Ceylon sapphire, the stone has a slightly sleepy appearance the softens its look, reminiscent of Kashmir sapphires. We think this stone is richer in color– the Lady Di sapphire seems bit dark, as you can see from the photos. We’ve surrounded it with over a carat of dazzling VS clarity diamonds of G to H color and set the gems in solid 14K white gold.

Princess Diana and Prince Charles wedding rings

Kate Middleton's engagement ring

Kate showing the ring

Based on our experience making jewelry, and seeing just how the royal ring was put together, we produced two separate components, the gem cluster and the ring shank/underbezel, on our new digital rapidprototype CAD/CAM system. Then  our goldsmith built the prongs as shown in the photos of the actual ring. Our method was actually much like the original for making this style completely by hand, with the exception that we produced the main parts with modern technology.

Rapid Prototype Parts

As we were briefing our goldsmith, Scott, on how the ring should be put together, the gems set, the piece polished, etc., he told us a very interesting story of his encounter with Lady Diana’s ring.

In 1987, early on in his career,  he was working for a high-end jewelery maker located in Palm Springs, CA.  Owner of a truly carriage trade business, she was preparing a line of jewelry items for Harrod’s, the famous department store, and was making a lot of trips back and forth to London. One day, after she returned from London, her shop foreman handed Scott a big sapphire ring and asked him to check the prongs for tightness and wear, mentioning that this was actually Lady Diana’s ring!

At the time, Scott had been working with a lot of large fine gemstones– his recall is that the ring was not impressive, especially compared to the other pieces he had been seeing.  This jives with the fact that while Diana chose her ring from a group of rings presented by the then Crown jeweller, Garrard’s of Mayfair, the same ring was a standard item, available in the Garrard catalogue, and the original cost was a nominal 28,500 British pounds.

Of course, now that it is one of the most famous pieces of jewelry in the world, the ring of Lady Diana was last valued at 250,000 pounds, due to it’s provenance. With the upcoming wedding and further association with the royals, who knows what it’s ultimate value will be. Kate Middleton, soon Princess Kate, and perhaps Queen Catherine, will certainly be a fashion setter for years to come- all the while, history is being made!

We’re very pleased with our version of this classic design, and though it is a truly luxurious and expensive piece, it’s ever so much more affordable than the ring William gave to Kate. Best of all, like Diana and Kate, it’s a one-of-a-kind.

Flash Patterns in Lightning Ridge Opal, I-14753

What makes opal such a fascinating gemstone? When asked what opal looks like, most people would probably first think of the typical white base opal with little sprinkles and twinkles of color.

White Opal with Pinfire/Chaff Pattern Play of Color

This unique display of color is a phenomenon correctly known as play of color, not fire as it is sometimes referred to. Any opal with play of color is commonly called precious opal .

The truly amazing thing about precious opal is the rich variety of patterns and color groupings we see.  Within the gem community, we classify these patterns with descriptive terms, the three basic groups of which are Pinfire, Flash, and Harlequin. Many precious opals display several patterns.

The most common pattern is called pinfire, also referred to as chaff, twinkle, and straw, often seen in white opal and in opal fossils, such as this opalized clam shell.

Pinfire in Opalized Clam Fossil

Other types of precious opal, such as black opal and boulder opal, display their play of color against a dark background. Since the appearance is much more dramatic, these types of opal are more sought after.

Lightning Ridge Black Opal with Chaff and Pinfire Pattern

Pinfire type patterns are often rather static, meaning their overall appearance is much the same from any direction. Other pattern types may change dramatically depending on the angle of view– this can add a dynamic element to the color presentation, but can also detract if the directionality is not optimal. It’s not unusual for opals to show more than one pattern.

Boulder Opal Pair with Pinfire and Broad Flash, I-8992

Flash patterns display larger areas of play-of-color that often shift or change color with movement. Variations: Broad Flash, Rolling Flash, Exploding Flash, Ribbon, Rainbow.

Broad Flash

Rolling Flash moves across the stone as the viewing angle changes or the stone “rolls.”

Rolling Flash, View 1

Rolling Flash, Mid rotation

Rolling Flash, View 3- rotated 180 degrees

Sometimes, rolling flash will present itself as a streak or “lightning bolt”

Lightning Bolt

Ribbon pattern in Brazilan Opal

Harlequin patterns have large, distinct, and usually rectangular patches of play-of-color with edges that touch each other. Variations: Checkerboard, Flag, Fish Scale, Flagstone. The colors of the pattern may change with viewing angle.

Harlequin Drop, Lightning Ridge Black

Harlequin Drop, View 2

Harlequin pattern in 7.75 ct. Lightning Ridge Crystal Opal

And finally, we occasionally find gems that speak to us in pictures or symbols. As a kayak fisherman, I have seen storm clouds and rain moving across the Sea of Cortez at morning sunrise– just as I see in this wonderful picture opal!

Baja Sunrise in Boulder Opal

Generally, the more dramatic the pattern, the more valuable. The more coverage of the face up appearance, the better.  The more colors, the better, especially if the colors include a full spectrum, or lots of reds and oranges. And of course, the more brilliant the colors, the more rare and valuable the stone will be. The best opals have full coverage with interesting patterns of many colors, brilliantly displayed. For a full description of how opals are graded, visit our opal grading page, and view more fine opals in our Gallery of Gems.

]]> http://www.mardonjewelers.com/blog/custom-jewelry/how-to-grade-opal-patterns-and-colors/feed/ 1 http://www.mardonjewelers.com/blog/custom-jewelry/what-is-the-true-padparadscha-again/ http://www.mardonjewelers.com/blog/custom-jewelry/what-is-the-true-padparadscha-again/#comments Wed, 16 Sep 2009 20:45:05 +0000 James L. Sweaney, CGA, FGA. GG http://www.mardonjewelers.com/blog/?p=1149

.86 ct Ceylon Padparadscha, Gem, no heat

We published this article February 2009 with good response.  Since Sapphire is the stone for September, we thought it appropriate to republish, with minor additions, editing, new pricing information and larger pictures.

Early in my career as a gemologist, while working the gem identification counter at the GIA Gem Trade Laboratory in Santa Monica, I fell in love with Padparadscha—a gemstone, not a girl. The privilege of seeing and handling a few magnificent specimens of this magical sapphire with the glorious sunset orange and pink color was like cupid’s arrow to the heart.

Since that time, I always seek out the dealers at the gem shows who’ve “got the goods” and have had the pleasure to own and sell a number of fine Padparadscha Sapphires. We recently sold this small but extremely fine example, a .86 ct. octagonal loupe clean Sri Lankan stone, perfect color and beautifully cut, certificates from GRS and AGTA showing no evidence of heat treatment.

A definition of the true color of Padparadscha can be the heated subject of discussion between gem aficionados and gemologists. The answer is that there is no one Padparadscha color—It’s a range of color that combines pink with orange with no secondary hues or overtones of brown. Even though it’s not a hue described in the GIA Color Description System, pink is almost always used to describe the color, rather than tones of red, even in the GIA literature.

The issue of what should properly be called Padparadscha was addressed by the famous Robert Crowningshield, gemologist extraordinaire, in “Padparadscha: What’s In a Name?” Spring, 1983, Gems & Gemology, pages 30-36. He concluded, “It is GIA’s opinion that this color range should be limited to light to medium tones of pinkish orange to orange-pink hues. Lacking delicacy, the dark brownish orange or even medium brownish orange tones of corundum from East Africa would not qualify under this definition. Deep orangy red sapphires, likewise, would not qualify as fitting the term Padparadscha’.” Note his use of the word “delicacy”— Padparadscha colors are commonly described as delicate, evoking the soft colors of dawn and sundown.

At the time of his article, perhaps due to issues about the goods from Africa and some of the new synthetics, Crowningshield did everything he could to describe “Padparadscha” like the classic Sri Lankan material, but called the term “too subjective” to use on GIA identification reports.

Today’s more modern usage at GIA and other labs such as GRS, AGTA, etc., is to use the term “Padparadscha Sapphire” as a variety name to describe natural sapphires that fall within the typical color range, with no brown. This designation adds significant value to this rare and exotic gem.

These lab reports may also include important information about origin and/or heating. True Padparadscha Sapphires may indeed be heat treated — within the gem trade, thermal enhancement is a normal and accepted practice, so long as the treatment is provable and/or disclosed. Those stones with no evidence of heating are more rare and valuable, bringing substantial premiums over heated gems.

This 18K brooch (with self-mined Deer Creek Fire Agate) by yours truly contains a suite of Sri Lankan Padparadscha sapphires that demonstrates the range of color most gem dealers and aficionados would accept as Padparadscha. Note the gradations from orange with pink to pink with orange, no brown.

Occasionally, “Pad” colors rise to a strong or even vivid level—this wonderful 4 3/4 carat stone from a Mardon custom ring is one of the more enchanting Padparadschas we have seen.

Note the different appearance in the two photos—you wouldn’t think it’s the same stone—but it’s the same stone, same camera, same photo-stage and lights, different lens, different day, minimal editing in Photoshop. For this stone, the orange hue dominates. Photographing gems can be a real challenge!

In some ways, we can more easily say what “Pad” is not rather than what it is.

Origin helps define Padparadscha. The classic locale originally known to produce the finest examples of “Pad” is Sri Lanka (formerly Ceylon), where crystals are found that are basically pink with an orange center. Because of the presence of chromium with no iron, these “Pads” often exhibit reddish fluorescence under UV radiation.

Sri Lankan Padparadscha Sapphires generally have a moderately strong level of saturation, lending the “delicate” colors a richness and impact for which they are famous. As noted, some rise to strong and rarely, vivid levels. Tone is generally medium light, though some will grade light or medium. Hue will span the range (as shown in the brooch), from orange with pink to pink with orange, with no brown tones whatsoever. Its’ been my experience that some of these Sri Lankan stones are more intense and orangy in incandescent lighting, perhaps due to fluorescence, similar to what you sometimes see with Burma rubies.

These Sri Lankan stones may or may not be thermally enhanced– generally, heating of this material seems  to be done at relatively low temperature, and in some cases, is difficult to detect. In our experience, stones known to have been heated have been documented by notable gem labs as “no evidence of heat treatment.”

About 1 in 100 pink sapphires from Madagascar, virtually all of which are heated, will change to a true “Pad” color, doubling to quadrupling its value. (Personal communication, Kevin Patterson)

The slightly brownish stones from Africa, particularly those from Tanzania and the Umba River source, were marketed in the 80’s as “African Padparadscha”, but the gem trade and consumers as a whole didn’t really accept the practice or the name. While some examples were attractive, that material never achieved the “brand recognition” and price of the stones from Ceylon. See Crowningshield, p. 32

A few more recent African stones from the Tunduru district, near Olduvai Gorge, are more similar in appearance to the Sri Lankan material, but these can take on a brownish overtone in incandescent light.

Orange sapphires are produced from southern India, from crystals that have a green “rind”. These stones are small and bright orange without the pink hue (personal communication, Kevin Patterson). I suspect this gorgeous very hot stone, vivid orange with no pink, sold from our collection, was from that locale.

A significant development in the story of Padparadscha occurred within the last decade when relatively large numbers of beautiful pinkish orange stones suddenly showed up in the Asian gem markets. Good science soon prevailed and proved these to be heated beryllium diffused yellow sapphires. Those who were selling this material didn’t disclose the treatment at first and tried to pawn them off as a new find.

Beryllium-diffused orange sapphires are not considered Padparadscha Sapphires, even though they may approach the color of the natural stones. Beryllium diffusion adds something to the natural matrix of the sapphire crystal, creating a pink centered yellow stone, the opposite of the classic Ceylon material. Gemologists can often detect these stones by immersing in methyl iodide and looking for the telltale yellow edge. (Be advised to use care and skill when working with methyl iodide!) Today, these goods are discounted ~ 70% and more at the wholesale level

And of course, synthetic sapphires, while they are truly sapphires of a similar color, are excluded within the gem trade as true Padparadscha—the term is always reserved for natural stones, mined from mother Earth. “Synthetic” or “Created” or “Brand Name” (Chatham, Inamori, etc.) should always accompany the description of such stones. Pinkish orange synthetic flux grown sapphires as well as Verneuil type synthetics are plentiful and can be very difficult to detect, especially the Verneuil stones.

Prices for fine Padparadscha Sapphires can retail from $600-2000 per carat for stones 1 to 2 carats graded good, $2,000-4,000 per carat for fine stones, with extra fine stones going for twice as much. 3 to 5 carat stones, great for rings, start around $1600 for good and range from $6,000 to 20,000 per carat and more for fine to extra fine stones. To quote the GemGuide, “Due to rarity, padparadscha sapphires are highly subjective and may have a large price variance above or below GemGuide prices.”

Daughter Jenny brought a very interesting article in Town and Country about Padparadscha to my attention.  The November 2008 had a great page of Cartier jewelry, all set with Padparadscha Sapphires. Priced from $375,000 to $2,000,000 — After all, it is Town and Country, and it is Cartier!  See page 133.

Finally, on the theory that the best way to know the true color of a Padparadscha is to train your eye by looking at good stones, I’ve included more photographs of Padparadschas I have known. I’d like to also invite you to visit Mardon in person—we‘d be happy to show you the real deal and answer any questions you might have about this wonderful gift of nature!

Ask about our Gem Brokering service if you’re in the market for Padparadscha– it’s our specialty! We know where to find the best stones and we know how to obtain proper documentation for these rare beauties. With a simple brokers fee, you’ll pay substantially less than a normal retail price.

Extra Fine 7 ct. Ceylon Sapphire in Mardon Custom Ring

Blue sapphires are found in many countries worldwide. The geological conditions in which they form determine the quality of the sapphire crystals. Some locales are known to produce exceptionally fine crystals, yielding extra fine gems. Each locale produces a range of gem material that shares common characteristics that are directly related to its unique geology.  The unique characteristics of each source allow us to classify many sapphires by their country of origin.

Country of origin can have a  significant effect on the value of a gemstone, especially when the stone is large and of fine quality. A certificate of origin from a top lab like GIA or GRS can make or break the sale of a fine stone. Determining the origin of a blue sapphire may be as straightforward as expert examination in a gemological microscope of inclusions and other characteristics, but it can require more sophisticated spectroscopic and other high level testing available only in the top labs.

Sapphire deposits are most often layers of gem gravel located in ancient river beds or flood plains. The crystals, eroded from the original hard rock, have been concentrated by time, wind and water into rich strata of water worn pebbles. Alluvial sources tend to produce high grade material because the erosive process break up inferior crystals.  Many sapphire mines are artisanal simple holes, pits, or tunnels dug by locals down into these alluvial gravels. Water is essential to wash these gravels for sorting. Hard rock mines are generally harder to work, often requiring arduous drilling and blasting to reach the gem crystals.

The “classic” sources discussed here are those that produce the finest gems. Perhaps the most famous source of blue sapphires is Kashmir. Found high in the mountains of northwest India, the original mines were hard rock deposits at the head of a small valley. Shortly thereafter, rich alluvial gravels were discovered beneath the valley floor. A frenzy of activity in the 1920′s effectively mined out these Kashmir deposits. A very small amount of material, generally inferior, still trickles onto the market, but most Kashmir sapphires of quality are old stones that have been bought and sold numerous times.

Superb 5 ct+ Kashmir Sapphire

Known for their soft “cornflower” blue color, as seen in the photo above, Kashmir sapphires are somewhat lighter in tone than top tier sapphires from other sources, usually about 6-7 rather than 7-8, and display a highly saturated vivid pure blue. Kashmir sapphires are further distinguished by their “velvety” look, the result of minute inclusions described as “flour”, which diffuse the light traveling thru the stone. The “sleepiness” of Kashmir sapphires is very distinctive and part of their charm. Kashmir sapphires are not heat treated.

Because of their reputation and the fact that little new material is being produced, sapphires documented to originate from Kashmir are avidly sought by collectors who seem to be willing to pay almost any price for a fine example. Fine Kashmir sapphires may cost twice as much as a comparable Burma sapphire, the next highest rung on the ladder– demand always exceeds supply, so prices for superior Kashmir stones can be truly astronomical. The ring above might bring $30.000 to $50,000 per carat in today’s market.

Next in rank is the Mogok tract in northern Burma. This age-old alluvial source has been heavily mined for centuries, despite brutal jungle conditions that make miners pay dearly for every stone. Current production of good material from Mogok is very limited. The Mong Hsu district of Burma produces little blue sapphire comparable to the Mogok material, so the term “Burma Sapphire” refers to Mogok material.

The best Burma sapphires are darker than Kashmir– their color often described as slightly violetish “royal” or “midnight” blue that is highly saturated. They are more transparent than Kashmir stones, and richer than Ceylon material with little or no color zoning. Burma sapphires are not usually heat treated, so good stones are often collector’s items, rare and pricey. A fine Burma sapphire of 5 carats may bring $20,000 per carat currently.

slightly violetish blue Burma sapphire

The island of Sri Lanka (Ceylon) produces a wider range of sapphire than any other classic source– in fact, it’s famous for “fancy” sapphires, i.e. colors other than blue, including the famous orange-pink “Padparadscha” color. It’s deposits are mainly alluvial, sprinkled about the island.

As well as a designation of origin, the term “Ceylon” is a descriptive term within the gem trade for the type of medium pure blue color the island’s sapphires are famous for. Ceylon blues may be light or dark, with color saturation that ranges from moderately strong (4) to vivid (6).  They are usually very transparent and lightly included so that their color can be described as “open,” but this clarity and bright color is often the result of heat treatment.

Ceylon sapphires often grade in the extra fine class, but because their relative abundance and the frequency of heat treatments, they don’t generally bring the collector’s premiums that we see with Kashmir and Burma goods. Nevertheless, top Ceylon stones of 5 carats can bring $10,000 to $15,000 per carat.

light Ceylon blue

medium Ceylon blue

dark Ceylon blue

As a source known for fine quality blue stones, Madagascar is the new kid on the block. This California sized island country, remotely situated off the east coast of Mozambique, has been mined intensively since the 1990′s. Like Sri Lanka, it produces a wide range of sapphire colors from numerous alluvial deposits. Mining is usually quite primitive, often artisanal. In general, top quality Madagascar blue sapphires resemble upper tier Ceylon stones, are usually heated and are priced similarly.

Fine Madagascar Sapphire

Numerous other occurrences of blue sapphire dot our planet, notably in Thailand, Cambodia, Australia, and Montana. Generally, these resources are not known for exceptional gems, but occasionally can yield upper tier stones that may rival high end stones from the more famous sources.

It’s very important to remember that a stone’s value is based on it’s quality and grading, and that all sources produce a range of material. A top quality stone from Ceylon can easily sell for more than a mediocre Kashmir sapphire.

It’s also important not to base your purchase on a certificate or piece of paper. Your personal taste is the most important criteria for the gem you will own, so train your eye by looking at gems and educate yourself about the finer points of your favorite gem.

Most of the top gemological labs that document sapphires and other colored gems don’t actually grade stones, but rather provide basic information about identification, country of origin, and presence or lack of treatment. When purchasing fine gems, it pays to consult with a gemologist or jeweler who is not only qualified to identify a gem, but also has the years of experience to provide you with realistic accurate grading and price information.

If you are in the market for a fine sapphire or other colored gem, take some time to read our Colored Stone Grading documentation– it will be worth your while. Peruse our Gallery of Gems to begin training your eye, and give us a call– we’ll be very happy to help you choose the best sapphire for your needs.

Well Formed Sapphire Crystal

Sapphire crystals form in the hexagonal system, with the long axis (z) intersected at 90 degrees by six axes (x,y) rotated 30 degrees apart. In this crystal, the z axis centers the crystal from long point to long point, and the six flat sides of the dipyramids are perpendicular to the x & y axes

An interesting property of many gem species is that they are doubly refractive, where light is polarized into separate rays of light which travel at different speeds, depending on the direction of the light through the crystal. Different speeds of light mean different wavelengths, different wavelengths of light mean different colors. This is the property of pleochroism, meaning that the material shows more than one color.

In blue sapphire, along the z axis, no polarization occurs and light behaves as if it were singly reactive. We call this the optic axis.

Looking in directions other than along the optic axis, we will see two colors (dichroism), violetish blue predominating along one axis, greenish blue along another. The color divergence between the two polarized rays is strongest when viewing the gem or crystal perpendicular to the optic axis. In gem cutting and gemological testing and identification, we use an instrument called a dichroscope which shows the two polarized rays side by side, and can also aid in identifing the optic axis.

In practical terms, this means that the best blue sapphires will be oriented with their table (the big flat facet on the top of the stone) perpendicular to the optic (z) axis, so that when we look at the stone face up, we are seeing non-polarized light, i.e. the purest color. Stones cut from poorly shaped crystals or fragments may be improperly oriented so that the violetish blue or greenish blue rays dominate.

Another characteristic of blue sapphire crystals is that they are often unevenly colored- note the patches of color in the crystal shown above. Corundum, the mineral of which sapphire (and ruby) are varieties, is allochromatic, meaning it is colorless when chemically pure. The color of blue sapphires is due primarily to impurities of titanium. The blue colors can concentrate in “zones” that manifest as bands parallel to the flat faces of the crystal. We often see dark blue streaks next to areas with little or not color.

Color zoning is almost always considered a negative feature, especially in upper tier blue sapphires. Good cutting technique and skill can minimize the effect of color zoning on the overall appearance of a sapphire, but all things being equal, a stone with no color zoning is more desirable than one with color zoning.

Inclusions in gems can profoundly influence the color appearance of the gem. One of the more common inclusions in blue sapphire is “silk,” which are ultra-fine crystals of the mineral rutile which form as the sapphire crystal cools. These appear as faint straight fibers which follow the hexagonal growth of the crystal.

Nicely matched pair of star sapphires

Silk is what gives a star sapphire its star– the lens shape of the cabochon cut focuses light on the minute silk fibers which are oriented at 60 degree angles to each other and the light is reflected out of the stone as sharp rays of light. The best star sapphires are relatively transparent, with just enough silk to generate a good star.

In excess, silk creates a milky look– If a sapphire gemstone or crystal is otherwise “gemmy” enough, it may be heat treated to high temperatures, causing the silk to reabsorb into the body of the sapphire, creating a more transparent gem, often enhancing or darkening the color appearance. The presence of silk “remnants” is one of the proofs of heat treatment.

On the positive side, very fine inclusions, rather like faint dust clouds within the gem, can give a sapphire a “sleepy” appearance than can be very desirable. Kashmir sapphires are known for their soft “velvety” appearance which, combined with their classic “Cornflower” blue, creates a unique look for these highly sought after gems. These stones are extremely rare today because little new material is being produced.

So we can see that the best blue sapphires are directly influenced by their parent crystals in several ways. They should be properly oriented, with the table perpendicular to the z axis, to show the best color. They should have even color, with no color zoning apparent, especially from the face up view. And they should be highly transparent- noticeable silk should be present only in star stones.

Classic Blue Natural Sapphire

Our clients often ask “What is the best color blue sapphire?” There are two answers– the obvious is that personal preference should dictate your color choice. Every person has unique abilities to perceive color, based on such things as age, health, culture and genetic gifts. Some people prefer light pastel colors, others prefer rich intense colors. The best color for you is the one that pleases, stimulates, or excites you!

The more complicated answer has to do with gem grading and market preferences, the physical characteristics of natural sapphires, the geological sources of sapphire including Ceylon, Burma, Kashmir, Madagascar, Thailand, Australia, and Montana, and the various methods of color enhancement and heat treatment of sapphire. We’ll begin by discussing gem grading and market preferences.

Color is a very complicated phenomenon in gemstones, presenting many challenges for gemologists and gem traders. We begin by grading the color of blue sapphires in terms of hue, tone, and intensity- for a thorough discussion of color grading gems, visit the color grading page at our Gallery of Gems.

Hue can be described as the name of a color, and relates to the actual wavelength of the visible light emanating from the gem. Some gem colors are described as two hues– such as green blue, signifying equal parts green and blue, or greenish blue for a color proportionately more blue than green. In grading gem colors, we normally emphasize the dominant hue by capitalizing it. For blue sapphire, the perfect hue would be simply Blue– not greenish Blue or violetish Blue. The hue of the sapphire below would be described as very slightly violetish Blue, while the hue of the second stone shown below and the blue sapphire ring shown at the beginning of this article is Blue.

very slightly violetish Blue sapphire color

Blue sapphire color

Tone is the relative position of a color on a 1 to 10 scale of light to dark. 1 being white, 10 being black. Blue sapphires can range from very pale blues that might be graded 2- 3 on the tonal scale to extremely dark blues that are graded 9.  The 4.5  ct. Ceylon sapphire in the estate ring shown below is somewhat light in tone, ~ 4.  The preferred tone for most blue sapphires that are used in jewelry is generally about 5 – 8.

blue Ceylon sapphire ring, tone ~ 4

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Intensity is sometimes referred to as vividness or color saturation. There is an optimum combination of saturation and tone for each hue known as the gamut limit. Yellow colors are most vivid in the tonal range of 2-3, greens around 7, reds and blues around 7-8. Over about 85% tone, blue colors rapidly lose intensity– many commercial grade sapphires are so dark they appear “inky.” We grade intensity on a scale of 1 to 6, 1 being brownish or grayish colors, 6 being Vivid colors.

Intensity is the one characteristic that really separates the very best blue sapphires from all the rest. Stones that are truly “vivid” stand out– for example, one to two carat “vivid” stones may be double or triple the value of stones graded “strong.”

Overly Dark Blue Sapphire

So, in terms of gem grading and market valuation, the color of the highest grade and most expensive blue sapphires will have a hue of Blue, a tonal range of  7 to 8, and Vivid saturation. Although color is the dominant factor in grading and valuing blue sapphires, clarity and cutting are also very important, especially in those over one carat. The best blue sapphires have the perfect color, high transparency, and great craftsmanship of cutting.

In parts 2,3, and 4 of this series, we’ll discuss the role of the physical nature of sapphire, the geological distribution of sapphire, and the impact of enhancements on the color of blue sapphire.

If you’re in the market for this wonderful gem, stop by our shop, visit our Gallery of Gems, or give us a call — we’ll be happy to search the markets to locate your perfect blue sapphire!