Bohemian Garnets

This Brooch Dates From the Third Quarter of the 19th Century. (Photo Courtesy the National Czech & Slovak Museum & Library)

“Bohemian garnets” are garnets mined in an area once known as Bohemia (it often refers to the entire Czech territory, including Moravia and Czech Silesia). They are the variety of garnet called pyrope (from the Greek words pyr for “fire” and ops for “eye”). Those found in Central Bohemia (in the north of the Czech Republic) are considered to be of the highest quality. 
The Bohemian garnet has been mined for over 600 years mostly dug at the mines of Meronitz, and chiefly in the northwestern part of the Czech Republic. The garnets are found in a gravel or conglomerate, resulting from the decomposition of a serpentine. Sometimes, however, they are found in the matrix. When this happens they are often associated with a brown opal. Most of the good quality the stones are small with those as large as approximately 1/4 inch and above being reported rarely. By the 19th century it was determined that the elements creating the intense red color in pyrope were Chromium and Manganese. The color ranges from fiery-red to ruby-red. The Bohemian garnet also possesses excellent clarity, transparency, and has a high refraction of light. This means that the stone has a remarkable sparkle and what has been described as an "inner glow".

The stone gained popularity in Europe in the 18th and 19th century also becoming a favorite of the Victorians. Traditional Bohemian design placed it's emphasis on the arrangement of the garnets, taking precedence over the metal chosen for a piece of jewelry. George Frederick Kunz cites in his book Rings for the Finger Garnet that rings were generally made of faceted, rose or cabochon cut Garnets in 14 or 18 kt gold. By the late 19th century larger Pyropes were typically brilliant-cut, resulting in very bright (red) stones, whereas the very small stones were usually rose-cut. 

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This Art Nouveau Style First Appeared in Individual Creations of Designers Rather Than in Industrial Mass Production. (Photo Courtesy The National Czech & Slovak Museum & Library)

An Example of the Mass Produced Items Typical of the Bohemian Garnet. (Photo Courtesy The National Czech & Slovak Museum & Library)

The introduction of larger scale manufacturing of garnet jewelry created mass-produced machine pressed metal settings and garnets of inferior quality. The majority of readily available "Bohemian Garnet" antique jewelry falls into this mass production category. While these pieces are beautiful in their own right, it should be noted that like any piece of jewelry rarity and individuality are valued much more highly. 

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Antique Pyrope Hairpin From the Smithsonian

Tantalizing Tourmaline

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Tourmaline by Sandy Hoy

October's birthstones are truly spectacular. 
Along with opal, tourmaline is October's birthstone. Both of these stones are gorgeous, but tourmaline is what I want to focus on today. For too long, tourmaline has only been seen as the dull green that is widely available. This is a shame. Tourmaline comes in such a wonderful wide range of colors and with a Mohs hardness of 7 to 7.5, it is durable enough to be used in any type of jewelry.

History
The first tourmaline was recorded in the 1500's in Brazil by a Spanish conquistador. The conquistador confused the vivid green of the tourmaline with that of the emerald. His mistake was not revealed until the 1800's when tourmaline was formally recognized as a distinct mineral species.
The name tourmaline comes from the word toramalli, which means “mixed gems” in Sinhalese (a language of Sri Lanka).  Dutch merchants started using the name to identify the multicolored, water-worn pebbles that miners found in the gem gravels of Ceylon (now Sri Lanka). The stones were brought to Europe in vast amounts by the Dutch East India Company as the demand for gemstones increased. As stated earlier, it was not until the 1800's when scientists were able to positively identify tourmaline as its own mineral species. As with many gemstones until the development of modern mineralogy, a stone's identity was based solely on its coloring, resulting in many stones being misidentified throughout time as ruby, sapphire, emerald, and so forth.

One of the earliest reports of tourmaline in the United States was in California in 1892. In the late 1800s, Tiffany gemologist George F. Kunz worked to make tourmaline an American gem, praising the tourmaline deposits of Maine and California; however, it was not the American market that the tourmaline mines both in the United states and in the Himalayas ended up attracting: it was the Chinese market. 
Because the miners became so dependent on Chinese trade, when the Chinese government collapsed in 1912 the US tourmaline trade collapsed with it. The California mines stopped or moved to sporadic production. Today, mines in San Diego County such as the Stewart Lithia mine at Pala still produce a small supply of gem-quality tourmaline.
The tourmaline trade expanded again during the first half of the twentieth century, when Brazil began to mine large deposits with superb quality. In the 1950s, additional finds were uncovered in other countries around the world, including Madagascar and Afghanistan which have have produced a stunning red tourmaline.

Pink tourmaline from Pala Mountain, Stuart Mine, San Diego. (Photo: Jeff Scovil)

Tourmaline Locations and Mining
Gem and specimen tourmaline is mined chiefly in Brazil and Africa. Additional locations include Sri Lanka, Tanzania, Nigeria, Kenya, Madagascar, Mozambique, Namibia, Afghanistan, Pakistan, and Malawi. Tourmaline is also sparsely mined in the San Diego County area of California.
Tourmaline (and some other large crystal gemstones) generally occur in an extreme form of igneous rock known as a pegmatite formation. Pegmatite is a type of igneous rock that forms during the last stages of magma cooling. Large crystals are fairly common in many types of igneous rock formations usually due to a slow rate of crystallization. With pegmatites, large crystals are attributed to low-viscosity fluids that allow the chemicals that make up a crystal to be highly mobile on an atomic level.
During the early formation of pegmatites, the magma usually contains a large amount of dissolved water and other chemicals such as chlorine, fluorine and carbon dioxide. Water is not removed during the early magma crystallization, so it becomes more concentrated as the crystallization continues. The presence of the water eventually forms large pockets in the rock. These super heated water filled pockets are also rich in the atoms of various chemicals. Within the pockets, the atoms have a much greater space to expand into than would be present elsewhere. This space combined with the extreme heat allows them to rapidly form into large crystals. The extreme conditions of crystallization in pegmatites have sometimes produced crystals that are several meters in length and weigh over one ton. 

The Colors of Tourmaline
Tourmalines make up a group of closely related mineral species that share the same crystal structure but have different chemical and physical properties. They share the elements silicon, aluminum, and boron, but contain a complex mixture of other elements such as sodium, lithium, calcium, magnesium, manganese, iron, chromium, vanadium, fluorine, and sometimes copper. It is these alterations to a tourmaline's chemical composition that directly influences its physical properties, including color. 

Many tourmaline color varieties have inspired their own trade names:

• Rubellite is a name for pink, red, purplish red, orangy red, or brownish red tourmaline, although some in the trade argue that the term shouldn’t apply to pink tourmaline.
• Indicolite is dark violetish blue, blue, or greenish blue tourmaline.
• Paraíba is an intense violetish blue, greenish blue, or blue tourmaline from the state of Paraíba, Brazil.
• Chrome tourmaline is intense green. In spite of its name, it’s colored mostly by vanadium, the same element that colors many Brazilian and African emeralds.
• Parti-colored tourmaline displays more than one color. One of the most common combinations is green and pink, but many others are possible. Including "watermelon" and Liddicoatite. 

Liddicoatite was first recognized as a separate mineral in 1977. The mineral was named in honor of Richard T. Liddicoat (March 2, 1917 – July 23, 2002), the second president of GIA who is often referred to as the “Father of Modern Gemology.” Most liddicoatite comes from Madagascar, including this slice from the Anjanabonoina pegmatite. Coutresy Harvard Mineralogical Museum, photo by Robert Weldon/GIA

Photo courtesy of GIA

Some tourmalines have a striking cat’s-eye effect called chatoyancy. Cat’s-eye tourmalines are most often green, blue, or pink. The "eye" often has a softer and more diffused than than other stones that display the same effect. This is due to the multitude of thin, tube-like inclusions inside the stone. The inclusions are larger than the inclusions of other stones, such as a cat’s-eye chrysoberyl, so the "eye" isn’t as sharp. Like other cat’s-eye stones, tourmaline needs to be cut as a cabochon to show the effect.

What's in a name? Paraíba Tourmaline

One of the most coveted and expensive of the varieties mentioned above is Paraíba.  It is a relatively "young" gemstone in that it was not discovered until the 1980, but its vivid blues hold the attention of the entire gem world. The reason behind the vivid colors is in fact why a true Paraiba stone is so rare and special. 
Normally, iron, manganese, chrome and vanadium are the elements responsible for the beautiful colors of tourmaline. The Paraíba tourmaline is different: its color is due to copper, an element which had never before been seen in a tourmaline. The presence of copper in the stone is as much what defines the tourmaline as a Paraíba as the location from which it came. Copper in high concentrations is responsible for the coveted radiant blue, turquoise, and green hues. 

Scientists have also (relatively recently) discovered that Paraíba tourmaline may also often contain manganese as well. When both of these two elements are present they produce a variety of vivid colors such as: emerald green, turquoise to sky blue, sapphire blue, indigo, bluish-violet, and purple. They can also result in more muted pale grey to violet-blue tones. 
Because of the stone's high value in an uncut state, Paraíba tourmalines are almost always custom cut to retain as much of the stones weight as possible, however the stones are still in sizes bigger than one carat. 

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The flawless 191.87 carats Paraiba tourmaline, The Guinness World Records largest, has been placed by experts in the field amongst the world’s rarest gems.

Recently scientists have discovered that Paraíba tourmaline often also contain manganese and it is the interplay between these two elements that creates the coveted colors. 

Since the late 1980s, the Paraíba area of Brazil has been a source of a strikingly colored variety of tourmaline called Paraíba tourmalines.

With Paraíba, the key factor is not size, but color; all factors being equal, the stone with the better color is a better choice.
During Paraíba tourmaline’s brief history, the gem has always been extremely scarce. However, new discoveries of copper-bearing tourmalines that resemble the vibrant, intense colors of the gems found in Brazil’s Paraíba region have also been found in other parts of the world. An article in the Spring 2008 issue of GIA’s Gems & Gemology scientific journal described copper-bearing gems present in Mozambique. Nigeria has become a source of these striking gems as well. With these new sources there comes the possibility that viable, commercial sources of this rare copper-bearing tourmaline might provide a larger supply of material. This brings a new problem for the niche Paraiba trade. If the stones of the same chemical composition and quality are being found outside of Paraiba does the trade name still apply? Only time and the market will tell. I personally think that the romance of a trade name should have little to do with the stone you are buying. The romance of a trade name aside, if the quality is good and the color is vibrant then that is what we should judge a stone by. 

The Lily Safra poppy flower brooch with diamond and tourmalines sold for $1,273,320 at Christie's Geneva, 5/14/2012. - © Christie's Images/The Bridgeman Art Library

The rainbow of colors that tourmaline has to offer the wearing is truly impressive. This stone has something to offer for everyone.  

The Sunset Sapphires: Padparasha

Sunset by Harry Winston, padparadscha sapphire and diamond ring.

On this final day of September it is only fitting to talk about one of the rarer and most sought after sapphire colors: the padparascha. 
Padparadscha is a color of sapphire that is commonly portrayed as a mixture of orange and pink colors. It has been referred to as a marriage between the color of sunset and that of a lotus blossom.  Padparadscha sapphires are considered among the most beautiful and valuable of the corundum gems. Prices for padparadschas vary greatly according to size, quality, and presence of treatments. At the top end, they may reach as much as US$50,000 per carat or more.
However the history of what actually defines a sapphire as a padparascha has changed over time and the question of just what qualifies a sapphire as a “padparadscha” is a matter of hot debate, even among experts.

Location: The original locality for padparadscha was Sri Lanka (Ceylon) and many purists today believe the term should be restricted only to stones from Ceylon. However, fine stones have also been found in Vietnam’s Quy Chau district, Tanzania’s Tunduru district, and Madagascar. Stones from each of these areas are often heat-treated and this is done at fairly low temperatures (1200°C and below) and such heat treatment is not always detectable.  Because of this diverse group of localities and the ease of treatments, many have come to rely on color as the defining characteristic of the padparascha sapphire, but here too we find debate and inconsistencies.

The Color Debate: The term padparadscha is actually a corruption of the Sanskrit/Singhalese padmaraga (padma = lotus; raga = color), a color similar to the lotus flower (Nelumbo Nucifera ‘Speciosa’). The padparadscha was born about twenty centuries ago, it is obvious
that over a period of about eighteen centuries men have built an idea of the padparadscha that has
varied considerably according to interests, periods and places. For instance, a number of the Lotus (Nelumbo nucifera [Nelumbium Speciosum indica] ) varieties and their respective colors have changed or ceased to exist over the years, leading to variations in what may constitute a "lotus color".

In the Western world, padparadscha has been defined as a Sri Lankan sapphire of delicate pinkish orange color; however, the delicate description of the padparadscha is not the norm in texts from the stones countries of origins. In fact, virtually all of the ancient texts that we have refer to the padparadscha as a type of ruby with the color of fire or sunset: a red-orange. In an early definition from the Indian subcontinent, dating from about 1200–1300 AD, the padparascha is described as:

That which spreads its rays like the sun, is glossy, soft to the touch (komala?), resembling the fire, like molten gold and not worn off is paümaraya [padmaraga]. - Sarma, 1984, Thakkura Pheru’s Rayanaparikkha – A Medieval Prakit text on Gemmology

Other definitions of also include references to vermilion and saffron coloring.  This paints an image of a much brighter and vibrant stone than the pastel versions that are prized today.
The jump from the vivid yellow-red coloring definition to that of the modern day criteria is linked to and  article by the GIA’s Robert Crowningshield published in 1983. Crowningshield provided an excellent summary of the origin of the term and what many considered to be ideal examples. Unfortunately, however, the GIA Library at the time did not include many Indian or Arab lapidaries.  The final definition was completely devoid of any early references to rich colors in the definition that he himself cited, but did not accept.
Crowningshield concluded by laying what we now know as the foundation for the color criteria of the padparascha:

It is clear that the term padparadscha was applied initially to fancy sapphires of a range of colors in stones found in what is now Sri Lanka. If the term is to have merit today, it will have to be limited to those colors historically attributed to padparadscha and found as typical colors in Sri Lanka. It is the 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.
Robert Crowningshield, 1983

On June 16–18 2005, members of the Laboratory Manual Harmonisation Committee (LMHC) met in Milan, Italy to consider a standardized definition of padparadscha which stands today: 

Padparadscha sapphire is a variety of corundum from any geographical origin whose colour is a subtle mixture of pinkish orange to orangey pink with pastel tones and low to medium saturations when viewed in standard daylight.
The name 'padparadscha sapphire' shall not be applied in the following cases:
If the stone has any colour modifier other than pink or orange.
If the stone has major uneven colour distribution when viewed with the unaided eye and the table up +/- 30°.
The presence of yellow or orange epigenetic material in fissure(s) affecting the overall colour of the stone.
If the stone has been treated as described in Information Sheets #2 and #3.
If the stone has been treated by irradiation.
If the stone has been dyed, coated, painted, varnished or sputtered.

In 2005, this 20.84-carat padparadscha sapphire fetched US$18,000 per carat at auction. Photo © 2005 Christie’s Images Ltd.

So within these criteria where would more intense padparadscha stones exist? Questions like this are often put to the test when stunning stones like that this one from Christie's auction house are presented to the public. As is pointed out by Richard Hughes author of Ruby & Sapphire the stone would clearly fall outside the Western guidelines of what is considered a padparadscha, but would it fall outside the guidelines of the country that first defined the stone? Should there be a gradient for tones within the category? 

Questions to Ponder: Richard Hughes is a proponent of such a grading system and I have to say I am inclined to agree with him. Yes, I believe that there should be standards of color; but as he points out, there are tone and saturation variations within blue, yellow, purple, pink etc., but they are still what they are. A pale blue sapphire is still a blue sapphire, so why should a darker padparascha not be simply a more saturated darker toned padparascha. I know that this may open up a debate about the defining of colors based on the gemologist's eye, but that is nothing new to the industry. One only need look to the debates that form around a ruby and a pink sapphire call! I am also troubled by the blatant disregard for the historical and ethnographic exclusion of definitions. Is it fair that padparascha is defined by outsiders without regard for the past? 

Sri Lankan padparadscha sapphire crystal,  8 by 5 cm; Collection: Paul Ruppenthal
Photo: Studio Hartmann From Gem & Crystal Treasures by Peter Bancroft

Just to make matters more confusing here is a recent description of the stone from Sri Lanka:
The term pathmaraga is a Singhalese term applied to a very special colour variety of corundum, so named after the lotus flower as its colour is sometimes akin to a variety of this flower…. The colour combination produces the rare and beautiful colour of a sunset red at its best as seen across a tropical sky.… The colour of pathmaraga is apparently a combination of yellow, pink and red, with mildly conspicuous flashes of orange.
Gunaratne and Dissanayake, 1995

Regardless of the definition the padpardscha is a beautiful stone and the gem industry will always argue because we exist in a world that is dictated by our eyes. Is there a perfect color? With the implementation of new color grading technology it is possible that we may narrow our scope further, though I secretly hope that we might actually expand it. I personally have a favorite, but I ultimately leave it to you (the consumer) since you are the ones that drive the market. Just as with any other stones, some may prefer the pastel, while others the darker. The choice is yours to make, even as the experts argue among themselves. 

Kathleen Marino MA, GG, NAJA, AJP

Special consideration: Richard Hughes author of Ruby & Sapphire; Franck Notari author of THE PADPARADSCHA SAPPHIRE from The University of Nantes