Blue Sapphire: Symbol of Serenity and Wisdom

Rose Dior Pop ring made with blue sapphire, diamonds, blue enamel and white gold. Photo: Dior

Saapphire is the blue brother of ruby, as both gemstones belong to the corundum family. When the word sapphire is used without color prefix, it is meant to describe the blue variety.

It is a minute content of iron or titanium impurities, or a combination of both coloring elements, that produce all shades of blue.

Blue is a calming color, it symbolizes serenity; it also stands for wisdom, stability and healing. In Hindi and Burmese, the word for “blue” means beautiful. In several Asian cultures, including the Chinese, blue was considered a variation of green; both colors were grouped under the term “qing”.

Of all the colors, blue is globally the most liked by both men and women; most likely because it is a calming and neutral color, which ranges from light turquoise blue to deep black-blue. Until the discovery of artificial indigo, blue was the rarest and most expensive color used in pictural art. This was due to the fact that blue is almost uniquely present in elements that cannot be transformed into pigments, for example the ocean and the sky. The ultramarine blue in antique paintings were derived from crushed lapis-lazuli.

Sapphire occurrences

Transcendence: A butterfly brooch with pavé diamonds, a 3.01 carat pentagonal-cut diamond for body, and vari-cut sapphires, mounted in titanium and gold, Cindy Chao the Art Jewel. Photo: Christie’s

Chemically, sapphire is an aluminum oxide, which is quite common in the molten magma below the earth’s crust. However, precious blue sapphire is rare, particularly those that display bright to richly saturated pure hues. The finest sapphires are formed in relatively iron-poor metamorphic rocks, which were transformed through a combination of pressure and temperature during mountain building.

Sapphires from Sri Lanka, Madagascar, Kashmir, and Myanmar (formerly Burma) are the most notorious sources for sapphires of formation.

Sapphires are also found in so-called basaltic rocks. These rocks reached the earth’s surface through volcanic activity, occasionally with sapphire crystals present in the lava. Unfortunately, basaltic rocks are iron-rich, which darkens and dulls the blue hue of sapphires. There are numerous sources of basaltic sapphires, e.g., Nigeria, Ethiopia, the Thailand-Cambodia-southern Vietnam region, China, and Australia. Thus, the geology created bright metamorphic sapphires in northern Vietnam and overly dark basaltic sapphires in southern Vietnam.

What is the finest blue?

Starfish clip, Schlumberger® Fleur de Mer clip in platinum and 18k yellow gold with sapphires and diamonds, Tiffany & Co. Photo: Christie’s

The array of color intensity of Sapphire ranges from very pale blue to very deep black- blue. While light sapphires can be used as bright gemstones, overly saturated deep blue stones are much less desirable. The reason is because they appear nearly black in incandescent light. A medium- intense blue, devoid of any greenish secondary color and/ or grayish undertone is the finest hue.

Sapphire is pleochroic, which means that in the directions perpendicular to the path of the pure blue, the color is a mixture of two different colors, namely yellow and blue in blue sapphire. From color science, we know that a blend of yellow and blue produces green. If the faceted sapphire is not perfectly oriented to display its purest possible blue through the table facet, some green might stain it. A greenish secondary color in a blue sapphire is like an oil-spill in water; it dramatically reduces its beauty and hence, its value.

The most valuable color is called “cornflower” blue. Actually, it is more than a color: it is a rare combination of medium to medium-intense pure blue saturation, with an exceptionally fine velvety texture that reduces extinction to its minimum. Extinction refers to the dark-appearing areas of a cut gemstone, when looked at it through the crown, without tilting the stone. Extinction is in direct competition with brightness: brightness is desirable and valuable, excessive extinction is unattractive.

The finest “cornflower” blue sapphires originate from the exhausted mines in Kashmir, and from some more recent discoveries in Madagascar; Sri Lanka produces occasionally some medium-saturated “cornf lower” blue stones. Kashmir sapphires can fetch more than USD 200,000 per carat when all quality parameters meet the highest standards.

Sinopé necklace, set with white gold, five oval-shaped cornflower blue sapphires from Madagascar (totalling 39,22 ct), lapis lazuli, brilliant-cut diamonds, Cartier

“Royal” blue is a richly and intense saturated blue, darker than “cornflower” blue, with sometimes a very subtle purplish modifier. The finest samples originate typically from the Mogok Valley in Myanmar. These Burmese “royal” blue sapphires are characterized by a glassy crystal quality with a rich blue body color combined with vivid reflexes of different hues of electric blue and some reddish flashes. Royal blue sapphires are also found in Sri Lanka, Madagascar, and Kashmir.

Royal blue sapphires and diamond necklace, Christie’s

A desirable color of beautiful, richly saturated sapphires from Sri Lanka is occasionally called “peacock’s neck” blue. This term should not be confused with the so-called “peacock sapphires” that show a color mix of toned greenish and bluish shades referring to the mix of color that ornate the peacock’s tail; these latter are of much lower value.

How to choose a blue sapphire?

Rose Dior Bagatelle ring from Haute Joaillerie collection, in 18K white gold, diamonds, purple blue sapphires, sapphire, Dior

Blue sapphire can match every budget, from USD 500 per carat to USD 100,000 per carat and more. Choose a stone that matches your budget and that you personally think is beautiful. Before buying a blue sapphire, look at it in daylight and in incandescent light. If it turns too dark in incandescent light, reject the stone, unless you enjoy it dark, or you like its particularly low price.

Most sapphires have a banded or patchy color distribution. When choosing your sapphire, consider that color-zoning is more disturbing when seen through the table and crown facets than through the sides of the gemstone. A sapphire with a uniform color spread when observed through the table is more valuable. Sapphires of basaltic formation are not only characterized by a darker blue and a darker tone, but also by a tendency to display more noticeable color-zoning. Also, because they generally occur in comparatively flat crystals, basaltic sapphires are often cut f latter than metamorphic sapphires, this “windowing” further weakens their brightness.

Beauty of color is by far the most important quality parameter in sapphire, but since sapphire is less rare than ruby, the clarity grade and cut quality are expected to be comparatively better.

Inclusions in sapphires

Blue sapphires on Piaget watches. From left: Piaget Treasures High Jewelry Watch, Limelight Gala High Jewelry Watch và Limelight Gala.

Impurities inside a gemstone are called inclusions. A high-quality faceted sapphire should be nearly eye-clean to eye-clean.

Sapphires with obvious inclusions are available at lower prices. It is the buyer’s choice if the beauty of color, the clarity grade, or the size should be compromised to match one’s budget. Opinions differ within various cultures and from person to person: while color can be a matter of taste, a lack of purity is there to stay!

Sapphires and rubies that have symmetrically oriented mineral needles are sometimes cut into a dome-shaped cabochon to produce six-rayed star stones. They are particularly sought-after, especially in eastern Asia, and fetch high prices if combined with a fine color and good translucency.

Buyer beware: Man-made sapphires and imitations have inclusions too. The presence of inclusions is not a proof of authenticity!

Why are some sapphires heated?

Riders of the Knight necklace with unheated sapphires and diamonds, Louis Vuitton

Sapphires are heated to alter their color and/or clarity to make them more sellable. Overly dark stones are heated to reduce the dark tone; milky-appearing sapphires and stones with a disturbing secondary color are heated to improve transparency and a to achieve a purer blue.

The heating of sapphires is a process performed in Sri Lanka since more than 1,000 years, this is why it is considered to be traditional or routine enhancement. Unless some newer heat treatments, known as diffusion-treatments, that involve the penetration of foreign elements into the stone.

Careful, do not be fooled by the appearance; each type and extent of treatment is represented in the market by a specific price range. Be careful when buying a gemstone: A gemstone disclosed as natural does not mean that it is not treated, it only means that it is not man-made.

Color terminology

Kissing by Boghossian bracelet combining moonstone and blue sapphires, BOGHOSSIAN

Color nomenclature has evolved over time and any color term that is not based on color science (e.g., Munsell color system) is subjective.

Popular color terms such as “cornflower” and “royal” blue, “pigeon’s blood” red, or “Muzo” green are trade and marketing terms; their descriptions are not standardized, therefore, not applied consistently within the trade and by the growing number of gemological laboratories. Many sellers tag their gemstones with fancy color terms to increase the marketability of their products; as a buyer, you can compare it to a child that points at every red car while screaming “Ferrari”!

Also, color terms are not exclusive to one single geographic origin. While a prestigious color term often pushes up the price of a gemstone, it does not necessarily increase its value. True value is dependent on beauty, rarity, and most possible objective quality parameters.

Additionally, the use of a color term to describe a stone does not guarantee its nature. For example, there are plenty of “cornflower” blue synthetic sapphires and glass imitations offered online. The exact wording must be understood by the buyer. A “cornflower” blue sapphire, a “cornflower” blue type stone, a Kashmir, or a Kashmir-like stone are quite different attributes. Even other industries have been inspired by prestigious gemstone appellations, advertising with Kashmir-blue cars, jade dishes made of glass, and emerald-green furniture.

Choose your gemstone wisely, with a gemological report that relates to the most rigorous criteria that match your budget. If a seller tells you that “cornflower” blue is nothing else than a medium-light blue or a green- blue sapphire, you know that you are dealing with the wrong person.

Lune Bleue necklace and earrings, from Stellar Times high jewelry collection, featuring sapphires from Sri Lanka and Madagascar combines with the radiant sparkle of diamonds, Louis Vuitton

Jewelries combining blue sapphire and diamonds, set in platinum, Shreve & Co

Harper’s Bazaar Vietnam