Navratna: Faith in the power of nine.

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An enamelled and gem-set Navratna necklace, India, late 18th century

(An enamelled and gem-set Navratna necklace, India, late 18th century; image courtesy of Sotheby’s.)

Here is a combination of gems, 9 in number (to be specific), that has the same kind of religious significance and sanctity all across Asia, regardless of the country and the cultural differences that almost always tend to separate one country or culture from the other.

Some of those countries that believe in the sanctity of the nine gems are India, Sri Lanka, Nepal, Myanmar, Vietnam, Cambodia, Singapore, Indonesia, Malaysia and Thailand.

(Illustrated maps of Southeast Asia and India; images courtesy of Pinterest.)

The nine gemstones in question are Ruby, Pearl, Red Coral, Emerald, Yellow Sapphire, Diamond, Blue Sapphire, Hessonite and Cat’s Eye. These are precious gems and according to Asian beliefs, only the purest of gems have the ability to protect an individual from disease, bad omens, demons, sins and any other sort of evil that may cause harm. Gems with impurities or flaws simply will not do.

Hinduism, Jainism, Sikhism and Buddhism are religions that support this belief system that hails the Navratna gems as sacred.

The celestial bodies associated with each gem are as follows:

Ruby – the Sun

Pearl – the Moon

Red Coral – Mars

Emerald – Mercury

Yellow Sapphire – Jupiter

Diamond – Venus

Blue Sapphire – Saturn

Hessonite – the Ascending Lunar Node

Cat’s Eye – the Descending Lunar Node

 

More details in the next post.

On Cutting Diamonds and Spotting Them.

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Diamonds can have visible inclusions and flaws as is the case for most gems and it is the decision of the diamond cutter regarding which inclusions can be kept and which of those must go. The structure and arrangement of the crystal also decide whether or not the diamond will be able to hold itself together. Despite it being a stone known for its hardness, it can shatter from the impact of a single blow which makes it quite a task; figuring out the right spots to create facets on the stone.

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(Clockwise: The Koh-i-noor diamond, The crown of the British monarch, Queen Victoria and Queen Elizabeth II, images courtesy of Pinterest and Getty Images.)

The cut of the diamond can also result in a significant reduction of the weight of the stone. An example of a diamond losing a significant amount of weight after being cut is the Koh-I-Noor. The Koh-I-Noor weighed 186 carats originally and after being re-cut, it weighed 108.93 carats which means it lost about 43% of its original weight.

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(Diamond cutting; image courtesy of GIA edu.)

The setting of the diamond is also taken into consideration, meaning, if it will be set in a piece of jewellery, whether or not it will be accompanied by other stones, the shape and size and colour of the other gems. Also taken into consideration is the faceting of the stone, how the light will reflect off of it. Shapes for the diamond are considered. Some of which are, oval, round, teardrop or pear-shaped, heart-shaped, cushion cut, to name a few.

Judging the hardness of a stone is a good way of figuring out if a stone is, in fact, a diamond, however, the downside is that a diamond can scratch another diamond so there is a possibility of inflicting damage on a perfectly good stone. In place of that scratch test, is a test on thermal conductivity that can be performed to judge the authenticity of a diamond. A pair of thermistors (a resistor that relies on temperature) is mounted on a copper tipped wire and one thermistor is used to create heat and the other to measure the temperature, if the stone conducts the energy in a matter of seconds, it proves its authenticity as a diamond.

After the faceting is done with, the diamond is polished; this is a rather long and tedious process and is taken on by technicians proficient in the procedure. The diamond is re-examined for flaws and inclusions which can then be removed if deemed necessary.

Between a Rock and a Hard Place

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(The Briolette of India; image courtesy of Famous Diamonds.)

We’ve established (in the previous post) what a task it really is for a diamond to form. The sheer time and pressure it takes simply to turn into a diamond in the rough is tremendous. After all of that time spent in very specific conditions the diamond takes shape.

It is the hardest mineral (to date) as per the Mohs scale.

For the sake of comparison let us turn our attention to the difference between Graphite and Diamonds for a minute; both of these happen to be allotropes (elements that are structurally different but come from the same element) of carbon. Graphite atoms are bonded in layers, which means there are weak covalent bonds holding it together, making it weak overall, whereas a diamond has a much larger structure and each atom is bonded with four other atoms and requires a whole lot of energy to be separated. This results in a hardness that proves to be an important characteristic of the gemstone.

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(Render of diamond and its lattice structure; image courtesy of Shutterstock.com)

The hardness of a diamond makes it the gem to beat where longevity is concerned; it isn’t easily damaged because it will probably take another diamond to make a mark on it which also means maintenance isn’t going to be much of a headache. A diamond in most cases, isn’t as susceptible to breakage as other gems either which makes it useful to cut into other stones, very useful for diamond cutters who help morph the rough stone into a gemstone with facets. It is used to cut glass as well. Its use as a semiconductor is still being developed.

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( Sketches of the Kohinoor and Regent from circa 1860, courtesy of cnn.com)

Diamonds are colourless and the ones with colour are a result of imperfections (fractures) in the stone or owing to the effect of radiation. The Gemological Institute of America (GIA) classifies the gradation of colour in diamonds from D to Z; D being colourless and Z being light yellow. Blue diamonds, like the Hope Diamond falls under a different grading scale and are referred to as fancy diamonds.

( For information on some famous diamonds, follow this link : https://narayanjewellers.wordpress.com/category/iconic-jewels/ )

 

 

 

Diamonds : Earthen and Interstellar.

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Diamond. A clear octahedral stone protrudes from a black rock.

(Diamond. A clear octahedral stone protrudes from a black rock; image courtesy of Wikimedia)

Diamonds do much more than just sit pretty and shine and a part of the clue is in the name; for instance, it’s derived from a word in ancient Greek which translates to unbreakable. Another fact about the diamond is that it takes a whole lot of pressure and just the right temperature to form; this process takes ages. Experts say that the ones that do surface are somewhere between a billion to 3 billion years old.

As if that is trying enough, it can take volcanic eruptions to carry the rocks carrying diamonds to the crust (surface) of the earth, this makes the volcanic pipes the primary source of diamonds and the alluvial deposits that may have been shorelines at some point or at the time the diamonds were found are the areas known as the secondary sources.

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(Formation of Diamonds; image courtesy of Siberian Times)

All of that information is about the diamonds formed on Earth, some diamonds, experts say, were parts of meteorites that were interstellar in origin and crashed on Earth, not formed on impact but pre-existing within the rock they travelled as a part of. Such impact crater sites have been found containing diamonds and this is owed to the fact that the impact served as the perfect contributor to the right combination of pressure and temperature for the diamonds to form and Popigai crater in Russia is said to be one such site.

This was the origin story (so to speak). More in the next post!

Stars of the Show.

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Star of India

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(The Star of India; image courtesy of Smithsonian Mag.com)

Asterism is the star of the show, quite literally. The Star of India is a star sapphire; meaning it is a rather large cabochon (shaped and polished instead of cut) gem that presents a luminous star shape on the surface of the stone. This gem in particular weighs a hefty 563.35 carats (112.67 g) and exhibits the star on both sides. It hails from the mines of Sri Lanka and has made a rather adventurous journey from the moment it was discovered up to the day it was finally safe in the showcase of the American Museum of Natural History in New York City, owing to the heist that the gem was a part of in 1964.

 

Star of Adam

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(The Star of Adam; image courtesy of Dailymail UK)

This oval beauty weighs a whopping 1,404.49 carats (280.898 g; 9.9084 oz.) and the estimated cost comes up to a figure between US$ 175 million and $300 million. This cabochon also has a star, six rayed and easily visible to the naked eye. The Star of Adam originated in the mines of Sri Lanka in a place called Ratnapur. It was named after Adam who the Muslims believe went to Sri Lanka and lived on Adam’s Peak after exiting the Garden of Eden and is currently in the possession of an anonymous buyer.

Star of Bombay

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(The Star of Bombay; image courtesy of Flickr)

A gift of love from one star to another, the Star of Bombay was purchased by Douglas Fairbanks, a silent movie actor from Trabert & Hoeffer Inc. in New York. The Star of Bombay was a stone that weighed 182 carats (36.4-g) and was set in a ring made of platinum that Mr. Fairbanks presented to Mary Pickford; also a silent film actress. It is a violet-blue in colour owing to the presence of titanium and iron and is apparently the namesake of Bombay Sapphire which is a British manufactured gin. On her death, the ring was donated to the Smithsonian as per Mary Pickford’s request where it has been on display ever since then.

 

 

Sapphires: Clarity, Cut and Carats.

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Silk inclusion that makes a star in sapphire

(Silk Inclusions in Sapphire; image courtesy of GIA edu)

Where clarity is concerned, inclusions occur in sapphires too but not to the extent that they occur in rubies. Some of these inclusions are needle thin and intersect each other are known as silk, while others can form colour bands or the shape similar to fingerprints.

Zircons, yellow 15.5 cts., and blue 23.75cts.

(Pleochroism; image courtesy of GIA edu)

These inclusions can cause the price of the gem to drop or soar depending on the effect they have on its clarity. The star effect, for instance, is called asterism and can hike up the price of the stone if the star is well-defined. Pleochroism is the phenomenon that occurs when the faceted stone shows off a different colour when looked at from a different direction. This is also quite an important characteristic of a sapphire.

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(Star Sapphire set in a ring; image courtesy of Sotheby’s)

Now, colour zoning refers to the areas of different colours in a stone which is characteristic of a sapphire. Cutters often cut the gem in accordance with a pattern that shows the colour in the best possible perspective. The star corundums are, of course, carved in a cabochon cut (not faceted) with the star visible in its centre, the rays equidistant from each other. The value of a star corundum is decided on the basis of the carats (weight), the colour, the visibility and intensity of the asterism (star effect).

The weight of these sapphires can range from a few to a hundred carats. The price can change according to the size of the gemstone depending on the quality of the stone which can be fine-quality or commercial quality (far more easily available).

(Clockwise: The Star of Adam, the Star of Bombay and the Star of India; images courtesy of Dailymail UK, Flickr and Smithsonian Mag.com respectively.)

The largest (famed) sapphire is the Star of Adam weighs 1404.49 carats, the Star of India weighs 563.4 carats and the Star of Bombay 182 carats and all of these stones were mined in Sri Lanka but more about these in the next post.

 

Sapphires in all their hues.

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When we think of sapphires, thanks to popular culture, what comes to mind is a gorgeous blue heart-shaped gemstone that the old lady threw into the ocean at the end of ‘Titanic’; the film (more about that necklace in another post).

File picture of a Christie's staff member wearing "The Blue Belle of Asia" in Geneva

(A Christie’s staff member wears “The Blue Belle of Asia”, a 392,52 carats sapphire, in this file picture taken during an auction preview in Geneva November 6, 2014; image courtesy of Reuters.)

Corundum is the oxide mineral that gives rise to the ruby and the sapphire, which is said to naturally occur in other colours as well; that is due to trace elements of other metals. The hardness of this precious stone measures 9 on the Mohs scale.

Where colour is concerned, sapphires are most popular as blue stones and colour plays a significantly large role when determining the value of the gem. Greater the intensity of the colour; all the more great is its value. Strongly saturated (vivid brightness) sapphires in medium tones that aren’t too dark command the highest prices in the gem market.

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(Geologic Occurrence of Corundum; image courtesy of Geology.com)

Pink sapphires belong to the “fancy” sapphire coloured category and are known among the circles of gem traders as padparadscha, whose colour lies somewhere between salmon to orange. These fancy sapphires fetch a high price in the market especially in comparison to other fancy sapphires (sapphires of other colours).

Coloured sapphires range from hues of lemon, peach, orange and red to olive green and colourless (also known as white) sapphires.

Zircons, yellow 15.5 cts., and blue 23.75cts.

(This 15.6 ct zircon displays an obvious pleochroic “bow tie” effect. Photo courtesy of Gia.edu by Joel Arem.)

Where clarity is concerned, inclusions occur in sapphires too but not to the extent that they occur in rubies. Some of these inclusions are needle thin and intersect each other are known as silk, while others can form colour bands or the shape similar to fingerprints. These inclusions can cause the price of the gem to drop or soar depending on the effect they have on its clarity. The star effect, for instance, is called asterism and can hike up the price of the stone if the star is well-defined. Pleochroism is the phenomenon that occurs when the faceted stone shows off a different colour when looked at from a different direction. This is also quite an important characteristic of a sapphire.

More on sapphires in the next post!

Columbian Treasures

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Mogul Emerald Necklace

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(The Mogul Emerald Necklace; image courtesy of the Smithsonian Geo Gallery.)

A Columbian discovery, this emerald made its way to India, where it was carved with a floral pattern reminiscent of the Mughal style. One belief is that it was carved instead of faceted because of the natural inclusions in the beryl which make the gem brittle in nature and susceptible to breakage. It is also possible that carving the stone instead of cutting facets was simply a conscious stylistic choice for that era of trends in jewellery making. The emerald is in the form of a pendant encircled by round diamonds and the necklace, in turn, is made up of two rows of diamonds; in all, the diamonds make up 50 carats worth. This emerald necklace is now a part of the National Gem Collection in the Smithsonian.

 

Mogul Mughal Emerald

(The Mogul Mughal Emerald; image courtesy of Christie’s.)

This is a rectangular tablet, dark green in colour also believed to be mined in Columbia. It is arguably one of the largest emeralds in the world, table-cut and weighing about 217.80 carats. It bears the carving of Arabic inscription on one side with a date marked as 1107 A.H. and a floral motif on the other side consisting of a rosette surrounded by poppies. Each of the sides has a hole drilled into it, possibly for attachments. Christie’s, New York auctioned off the emerald to an anonymous buyer for 2.2 million dollars sometime around or after 2001. The gemstone is reported to be in the Museum of Islamic Art, Qatar as of today.

 

Guinness Emerald Crystal

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(The Guinness Emerald Crystal; image courtesy of Internet Stones.)

This emerald used to be one of the largest natural emerald mined from Coscuez; one of the three significant mines in Columbia, the other two being Muzo and Chivor. 1,759 carats in weight, this emerald is bright green in colour and is an elongated crystal with twelve sides (dihexagonal). The emerald is somewhat translucent and there are fissures towards the bottom of it that are quite clearly visible to the naked eye (as is the case for most emeralds where visibility is concerned). It is currently in the care and possession of the Banco Nacionale de la Republica in BogotÃ, Colombia.

 

Mackay Emerald Necklace

Mackay Emerald Necklace - Art Deco diamond and platinum by Cartier circa 1931

(The Mackay Emerald Necklace; image courtesy of Pinterest.)

This spectacular gem made its way from the mines of Muzo to Cartier’s, who set it in a necklace. The emerald weighs 167.97 carats and it serves as a pendant surrounded by emeralds and round brilliant and step cut diamonds and is set in platinum. It was a wedding present to Anna Case, a prima donna of the New York Metropolitan Opera from her husband Clarence Mackay; which is where it got its name. It was donated by Anna Case Mackay to be a part of the National Gem Collection in 1984 and is currently on display and in the possession of the Smithsonian Institute.

Green Beryls and Emeralds.

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(Beryl sample; image courtesy of Geology.com)

Beryl is the mineral family from which the emerald hails and is distinguished from other gems by its green colour. The emerald is considered one of the four cardinal gems. The green in this gemstone comes from trace amounts of chromium, vanadium and iron (to an extent) and the variations in the trace amounts of these elements that exist in the stone are what determine  its (the emerald’s) worth and marketability. It is also this very same colour that holds the emerald as the standard for every green gemstone out there.

Since colour plays a major role in distinguishing one gem from the other (in most cases), we’ll begin with that. Emeralds range, in colour, from a yellowish green to a bluish green, the darker the tone of green in a stone, all the more obvious it is that the gem is an emerald. A light coloured stone (yellowish) suggests it may be a green beryl and not the cardinal gem.

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(The Flagler Emerald From the Estate of Mary Lily Kenan Flagler; image courtesy of Sotheby’s.)

Emeralds are mostly cut in a cabochon (not faceted) and that can be owing to the disparity in hues and saturation occurring due to the fissures in the stone. Other than cabochon and an oval cut, emeralds have a certain cut that is rectangular in shape, faceted on the top.

Clarity, where the emerald is concerned, can practically be judged by the naked eye and this is because the fractures occur close to the surface; making the emerald susceptible to breakage. The stone has a hardness of 7.5 to 8 on the Mohs scale which should make it a hard stone but because of the surface breaking fractures and inclusions that occur in most emeralds, the stone isn’t considered durable but brittle.

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(Emerald necklace by Cartier; image courtesy of Sotheby’s.)

In order to correct these sorts of impairments and to strengthen the gem while increasing the clarity, the emeralds are treated with oils that seep into the fractures and improve clarity of the stone significantly. Having said that, emeralds that have been treated with oils are worth less in most cases where the market for gemstones is concerned.

More about Emeralds in the next post.

The Sunrise, the Liberty Bell, the Rosser Reeves and the DeLong Star.

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The Sunrise Ruby

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(The Sunrise Ruby Ring by Cartier; image courtesy of Sotheby’s)

I am like a ruby held up to the sunrise.

Is it still a stone, or a world

made of redness? It has no resistance

to sunlight. The ruby and the sunrise are one.

  • Rumi (excerpt from Sunrise Ruby)

 

Sufi poet of the 13th Century, Jalaludin Rumi (1207-1273) wrote the poem Sunrise Ruby, after which this famous gem has also been named. The Sunrise Ruby weighs 25.59-carats (5.1 g) and is pigeon blood red in colour. Burmese in origin, discovered in Mogok, this gem is considered one of the most rare of its kind. The stone is mounted on a ring in the middle of two heptagon-shaped diamonds that weigh 2.47 carats (0.49 g) and 2.70 carats (0.54 g) respectively and the design credited to Cartier. The ruby ring was auctioned off to an anonymous Swiss buyer at a Sotheby’s auction for US$30.42 million on the 12th of May 2015  in Geneva, Switzerland. It is quite the record for a ruby as rare as this one; in comparison to diamonds.

 

The Liberty Bell Ruby

Liberty Bell Ruby

(Jim Stein, owner of Stuart Kingston Jewelers, poses with a custom case holding the Liberty Ruby; image courtesy of The Daily Mail.)

This ruby in particular is carved from a single stone in the shape of the Liberty Bell (an iconic representation of American Independence) the carved bell is bordered by 50 white diamonds (standing for the 50 different states) and above the bell is an eagle (another symbol of the United States). It is the largest mined ruby of its size and weighs close to 4.5 pounds. It was discovered in the mines of Africa. The ruby was carved by Alfonso de Vivanco for the Kazanjian Brothers jewellery company. Unfortunately, the Liberty Bell Ruby was stolen among other valuables worth more than $4 million while it was being held at the Stuart Kingston jewellery store in Wilmington, Delaware. The thieves were arrested later on but the whereabouts of the Liberty Bell Ruby remain unknown to this day.

 

The Rosser Reeves Ruby

(L to R: The Ruby on display at the Smithsonian; image courtesy of Hyper Physics.edu and Rosser Reeves the advertising mogul; image courtesy of Branding Strategy Insider.)

This particular gem is of Sri Lankan origin and is named after Rosser Reeves who was an American advertising executive and a pioneer in his field, he published a book called Reality in Advertising which is taught at Harvard Business School. It is said that this stone weighing 138.7 carats (27.74 g) was carried around by the advertising mogul as a lucky stone. The Rosser Reeves Ruby is a six-rayed (well-defined) star ruby; one of the finest of its kind with vivid colour and clarity. Rosser Reeves donated this gem to the Smithsonian in 1965 where it has been put on display since then.

 

DeLong Star Ruby

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(The Delong Star Ruby in the American Museum of Natural History in New York; image courtesy of Pinterest.)

This gem is a 100.32-carat (20.064 g) oval cabochon (shaped and polished but not faceted) star ruby. A ruby of Burmese origin, it is named after the Manhattan dowager Edith Haggin DeLong who donated the ruby to the American Museum of Natural History, New York in 1937. In 1964, a heist took place wherein the DeLong Star Ruby among other precious jewels was stolen, it was exchanged for a ransom and has been returned to the custody of the museum.