Gemstones Education

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Please feel free to click on the link below to read about colored stone grading system

Color

 

Clarity

 

Cut

 

Here you can learn about the most common gemstones available.
Please feel free to click on the link to learn more about each gemstone.

Alexandrite

Amethyst

Aquamarine

 Chrysoberyl

 Emerald

Garnet 

 Jade

Kunzite

 

 Morganite

Onyx

 

 Opal

 Pearl

 Peridot

 Ruby

Sapphire

 

 Topaz

Tourmaline 

Turquoise

 

Alexandrite

 

 If you love magic, especially the magic of science, you'll love alexandrite, the color-change gem. Outside in daylight, it is a cool bluish mossy green. Inside in lamplight, it is a red gem, with a warm raspberry tone. You can watch it flick back and forth by switching from fluorescent to incandescent light. Alexandrite is a gem variety of the mineral chrysoberyl discovered in 1830 in Czarist Russia. Since the old Russian imperial colors are red and green, it was named after Czar Alexander II on the occasion of his coming of age. Today, fine alexandrite is most often found in period jewelry since newly-mined gems are extremely rare. You'll see fine gems offered at auction with impressive estimates. The original source in Russia's Ural Mountains has long since closed after producing for only a few decades and only a few gemstones can be found on the market today. Material with a certificate of Russian origin is still particularly valued by the trade. Some alexandrite is found in Sri Lanka, Zimbabwe and Brazil, but very little shows a dramatic color change. For many years, alexandrite was almost impossible to find because there was so little available.Then in 1987, a new find of alexandrite was made in Brazil at a locality called Hematita. The Hematita alexandrite shows a striking and attractive color change from raspberry red to bluish green. Although alexandrite remains extremely rare and expensive, the production of a limited amount of new material means a new generation of jewelers and collectors have been exposed to this beautiful gemstone, creating an upsurge in popularity and demand.    

 

 

Amethyst 

 

Quartz is found in abundance from every corner of the earth. In its purest form, quartz is colorless, but is most prized for its purple variety- amethyst. Purple has long been considered a royal color, so it is not surprising that amethyst has been so much in demand throughout history. Fine amethysts are featured in the British Crown Jewels and were also a favorite of Catherine the Great and Egyptian royalty. Great thinkers like Leonardo da Vinci believed that amethyst could dissipate evil thoughts and quicken the intelligence.
Amethyst, the traditional birthstone for the month of February, is available in small and large sizes, although as with all gemstones, very large sizes in rich, deep colors have always been rare. Designers celebrate amethyst as the ideal choice for jewelry because of its regal color, variety of sizes and shapes, affordability and wide tonal range from light to dark purple.
Ametrine
Occasionally, Mother Nature combines the colors of amethyst and citrine into a single, exciting gemstone we call ametrine. The Anahi Mine in Bolivia became famous in the seventeenth century when a Spanish conquistador received it as a dowry when he married a princess from the Ayoreos tribe named Anahi. Ametrine was introduced to Europe through the conquistador's gifts to the Spanish queen.
Ametrine is as affordable as regular amethyst or citrine, and you can have both gemstones for the price of one. Ametrine is especially inexpensive when you consider that it comes from only one place.   


   
Aquamarine

 

The very name aquamarine brings to mind the limpid, clear blue tint of the sea. Legend says that Neptune, the King of the Sea, gave aquamarine as gifts to the mermaids, and from then on, it has brought love to all who have owned it. Aquamarine was long thought to have a soothing influence on married couples, making it a good anniversary gift.
Aquamarines are found in a range of blue shades, from the palest pastel to greenish-blue to a deep blue. While the choice of color is largely a matter of taste, the deeper blue gemstones are more rare. Remember that Aquamarine is a pastel gemstone, and while color can be quite intense in larger gemstones, the smaller aquamarines are often less vivid.
This elegant colored gemstone is the birthstone of March and is the symbol of youth, hope, health and fidelity. Aquamarine was long thought to have a soothing influence on married couples, making it a good anniversary gift.
Aquamarines are mined in a number of exotic places including Nigeria, Madagascar, Zambia, Pakistan and Mozambique, but most of the gemstones available today come from Brazil.
Many aquamarines are greenish when mined and cut. For those who prefer a purer blue, these gemstones are heated to enhance their blue color permanently. Some aquamarine fanciers prefer the greenish hues, saying the greener tones remind them more of the sea. The color tones of aquamarine are subtle and varied. Their soft luster is a wonderful addition to any natural colored gemstone jewelry collection.     

 

 Chrysoberyl

 

Chrysoberyl is not one of the best known gemstones. Its rarest variety alexandrite, however, is quite well known, although the number of people who have heard of alexandrite is probably 100 times greater than the number who have ever seen one, and 1,000 times greater than the number who have ever owned one.
Chrysoberyl is composed of Beryllium Aluminium Oxide, is harder than topaz, and includes a variety known as cat's eye, in addition to alexandrite which we have already mentioned.
Most chrysoberyl is green or yellow-green, but some is brown. The rare alexandrite shows a colour change from green to red, and cat's eye has a strongly banded appearance which is well described by its name, and is also usually green or yellow-green.
Chrysoberyl was very popular in Victorian and Edwardian times, when it was often inaccurately called chrysolite. It is possible that supply was more plentiful around that time, certainly it is not frequently seen nowadays.


Emerald

 

The ancient Egyptians mined emeralds nearly 4,000 years ago, and Cleopatra was an avid collector. South America's rich bounty of emeralds was discovered by 16th Century Spanish explorers who found large emeralds in the possession of the Aztecs and Incas. Believed by the ancients to empower the owner with foresight into the future, emerald is regarded as an amulet for good fortune
Emerald, to many, symbolizes rebirth and the abundance of the life force. The rich green hue brings to mind the regeneration of life in spring and hope of new possibilities. Emerald is the birthstone for May and a talisman for Gemini.
Spring can also be seen in the network of inclusions in the depth of the emerald that the French call the jardin, or garden, because it resembles foliage. The inclusions are like a fingerprint, giving each emerald a distinct personality and distinguishing them as truly natural gemstones.
Today, most of the world's emeralds are mined in Colombia, Brazil and Zambia. Emeralds can be cut in a variety of different shapes, ranging from the traditional rectangular step-cut, known as the "emerald cut," to rounds, ovals, squares and cabochons.
Early gemstone merchants sought to purify the transparency of their emeralds by immersing them in clear oils or paraffin. They found that clear oils and waxes rendered surface fissures less visible to the eye. Today, we have many sophisticated technologies with which to clarity-enhance emeralds. In addition to the oils and waxes of ancient methods, we now use clear resins to penetrate the open fissures surfacing in the stones. Hardeners are often added to solidify these liquids. This step prevents the resin from evaporating, thus making the clarity enhancement more permanent than oiling or waxing the gem. Although emerald itself is quite durable, the garden of inclusions may make individual gems vulnerable to damage if handled roughly.   

 

Garnet 

 

Garnet traces its roots to the Nile Delta in 3100 B.C., where Egyptian artisans would craft the gemstone into beads or inlay them into hand-wrought jewelry. Noah used garnet as a lamp on his bow as he cast about on the ocean. Garnet received its name from the ancient Greeks because the color reminded them of the "granatum," or pomegranate seed.
The versatile garnet comes in a virtual rainbow of colors, from the deep red Bohemian Garnet to the vibrant greens of the Russian demantoid and African tsavorite. The oranges and browns of spessartite and hessonite hail from Namibia and Sri Lanka and the subtle pinks and purples of the rhododendron flower, are also yours to explore.
Garnet is the traditional birthstone for the month of January, however, red need not be your color of choice if you are born in this month. Rich orange and golden hues, striking greens, petal soft colors of violet and lavender, all await your selection.
Most commonly found in round, oval, and cushion cuts. Availability depends on variety: tsavorite is very difficult to find in sizes above a carat or two, while rhodolite garnet is available in larger sizes.
This durable and brilliant gem is easy to care for with mild dish soap: use a toothbrush to scrub behind the gemstone where dust can collect.    

 

Jade  

 

Since at least 2950 BC, jade has been treasured in China as the royal gemstone. Jade is a bridge between the spiritual and the material world. Jade was thought to preserve the body after death and can be found in emperors' tombs from thousands of years ago. One tomb contained an entire suit made out of jade, to assure the physical immortality of its owner. In Central America, the Olmecs, the Mayans and the Toltecs also treasured jade and used it for carvings and masks. The Aztecs instituted a tax in jade, which unfortunately led to the recycling of many earlier artworks.
Jade is usually cut into smooth dome shapes called cabochons. Jadeite bangles are also very popular in Asian countries. Beads are also very beautiful and some important jadeite necklaces made during the art deco period have fetched hundreds of thousands of dollars in auctions. Most treasured for its vivid greens, jade also comes in lavender, pink, yellow, and white.
While jadeite is mined today primarily in Myanmar, small quantities can be found in Guatemala.
Jade is very durable and tough. Clean with mild dish soap: use a toothbrush to scrub behind the stone where dust can collect.   

 

Kunzite

 

Surprisingly Kunzite was discovered in the United States, early in the twentieth century. Even its name has American roots: this pink gem variety of the mineral spodumene is named in tribute to George Kunz, the legendary gem scholar, gemologist, and gem buyer for Tiffany & Co at the turn of the century. The author of The Curious Lore of Precious Stones, Kunz searched the globe for old stories and legends about gems as he searched for new varieties and new deposits.
Kunzite was first found in Connecticut, USA. But the first commercially significant deposit was discovered in 1902 in the Pala region of California, where morganite beryl was also first discovered. The name was a brilliant marketing move: the miners named the gem after its most likely customer, Kunz.  Morganite was named for the customer’s customer: J.P. Morgan.
Today most kunzite is mined in Brazil, Afghanistan, and Madagascar. Kunzite is often found in association with morganite and pink tourmaline, the other popular pink gemstones.
Kunzite is relatively hard, but should be handled with care because, like diamond, it has a distinct cleavage. A sharp blow, if it lands in the wrong place, can break it in two. Kunzite should also be protected from heat and continued exposure to strong light which may gradually fade its color. Clean with mild dish soap: use a toothbrush to scrub behind the stone where dust can collect.    

 

Morganite 

 

Morganite was first discovered in California in the early twentieth century. A rich gem find of tourmaline, kunzite, and other gems outside San Diego started a gem rush in the region.  Morganite was an exciting new discovery, one that drew the attention of the world's most important gem buyer: George Kunz of Tiffany & Co. He decided to name it in honor of his biggest customer: millionaire bank tycoon J.P. Morgan, who was an avid gem collector.
Although its color is pastel, it has a lushness rare in pink gemstones.
There are deposits of this gemstone in Brazil, Mozambique, Namibia, Afghanistan, and Russia. Morganite is a durable gemstone perfect for everyday wear. Clean with mild dish soap: use a toothbrush to scrub behind the stone where dust can collect.    

 

Onyx 

 

The name comes from the Greek word onux , which means fingernail. According to Roman Mythology, Cupid cut the divine fingernails of Venus with an arrowhead while she was sleeping. The fates turned the clippings into stone so that no part of the goddess would ever perish. Black isn't normally the color one associates with fingernails, but in Greek times, almost all colors of chalcedony from fingernail white to dark brown and black were called onyx. Later, the Romans narrowed the term to refer to black and dark brown colors only.
Even in Roman times, the black color of onyx was usually enhanced by man. More than 2000 years ago, Roman historian Pliny described a traditional technique for darkening onyx that is still in use today. The onyx is soaked in sugar water, then placed in strong acid. After boiling for two hours, the acid eats away the sugar and water, leaving pure black carbon. Today cobalt dye is also used.
Durable and easy to care for, onyx has a hardness of 7 and enviable toughness even when carved in intricate designs. The seal rings worn by ancient Romans are still in fine shape today. Clean with mild dish soap and let dry.   

 

Opal 

 

Revered as a symbol of hope, fidelity, and purity, opal was dubbed the Queen of Gems by the ancient Romans because it encompassed the colors of all other gems. Opal is prized for its unique play of color, the ability to diffract light into flashes of rainbow color.
Opal occurs in different colors, ranging from semi-transparent to opaque. The most common is white opal. Crystal or water opal has a colorless body. The most valued variety, black opal, has a dark blue, gray, or black body color. Boulder opal combines precious opal with the ironstone in which it forms. Bright yellow, orange, or red fire opal are quite different from the other varieties of opal. Their day-glo tones, which are translucent to transparent, are beautiful with or without play of color. Opal, along with tourmaline, is the birthstone for October and the suggested gift for the fourteenth anniversary.
Today's supplies of opal come primarily from Australia, Mexico and the United States. Most opals are not faceted but cut into rounded or free-form cabochons that enhance their play of color.
Although opal is rarely enhanced by methods other than cutting and polishing, opals can be treated to bring out their play of color. One technique is to immerse white, gray, or black opal in a sugar solution and then in strong sulfuric acid, which carbonizes with the sugar and leaves microscopic carbon specks that blacken the body color, making its flashes of color more visible. Opals can also be permeated with colorless oil, wax, resin, plastic, and hardeners to improve their appearance and durability. Occasionally, some thinner or translucent opal may be painted with a black epoxy on the backside of the gemstone to darken the body color and improve the play of color. Fire opal is not commonly enhanced.
Opal, with or without enhancement, should be treated with some care. Opal is softer than many other gemstones and should be stored carefully to avoid being scratched by other jewelry. It should also be protected from blows, as exposed corners can chip. Opal should not be exposed to heat or acid.   

 

Pearl 

 

According to ancient Chinese legend, the moon holds the power to create pearls, instilling them with its celestial glow and mystery. Pearls have been treasured for their lustrous, creamy texture and subtle iridescent reflections since the dawn of humankind.
Pearls are unique in the world of colored gemstones since they are the only gemstone formed within a living creature. Because natural pearls are so rare and difficult to recover from the ocean's depths, man invented the technique of culturing salt and freshwater pearls from mollusks carefully seeded with irritants similar to those produced by nature. The painstaking effort of culturing is one of the most dramatic examples of man's quest to coax beauty from nature.
Today, cultured pearls are grown and harvested in many parts of the world including the fresh waters of the Tennessee River. The majority of cultured pearls come from Japan, China and the South Pacific.
Cultured pearls come in many beautiful colors including: gold, yellow, champagne, pink, peach, lavender, gray and black. Cultured pearls come in many shapes and sizes, and can be acquired in both graduated and uniform strands. They can be purchased singly or in pairs for rings, pendants and earrings. June birthdays and third and thirtieth anniversaries are celebrated with the gift of pearls.
Due to demand for perfectly matched white pearl strands, cultured fresh and saltwater pearls are often bleached to achieve a uniform color. They may also be polished in tumblers to clean and improve their luster.
Dyes, heat treatment, and irradiation are sometimes applied to produce a wide range of hues such as yellow, green, blue, purple, gray, and black in freshwater and Akoya cultured pearls. Some South Sea cultured pearls are bleached to lighten their hue, but most South Sea and Tahitian cultured pearls are not subjected to enhancements to create or improve their color.
Pearls require special care because they contain calcareous crystals that are sensitive to chemicals and acids. To care for your cultured pearls, avoid using perfume, hairspray, abrasives, solvents, and nail polish removers while wearing them. Like your skin, cultured pearls contain water and may dehydrate and crack if exposed continuously to arid conditions.    

 

Peridot 

 

Peridot is treasured in Hawaii as the goddess Pele's tears. The island of Oahu even has beaches made out of tiny grains of peridot.  Although Hawaii’s volcanoes have produced some peridot large enough to be cut into gemstones, virtually all peridot sold in Hawaii today is from Arizona, another state with extreme geology. The fresh lime green of peridot is its distinctive signature. Its spring green color also is ideal with sky blue.
Today most peridot is mined, often by hand, by Native Americans on the San Carlos Reservation in Arizona. Peridot found here is beautiful in color but relatively small in size. Faceted peridot from Arizona is rare in sizes above five carats. Fine large peridot are found in Burma and large quantities of peridot are also mined in China. In 1994, an exciting new deposit of fine peridot was discovered in Pakistan, 15,000 feet above sea level in the far west of the Himalaya Mountains in the Pakistanian part of Kashmir.
Peridot, the birthstone for August, is harder than metal but softer than many gemstones. Store peridot jewelry with care to avoid scratches and protect from blows. Because peridot is sensitive to rapid changes in temperature, never have it steam cleaned and avoid ultrasonics. Clean with mild dish soap: use a toothbrush to scrub behind the stone where dust can collect.   

 

Ruby 

Celebrated in the Bible and in ancient Sanskrit writings as the most precious of all gemstones, rubies have been the prized possession of emperors and kings throughout the ages. Ruby's inner fire has been the inspiration for innumerable legends and myths, and to this day, no red gemstone can compare to its fiery, rich hues. It was believed wearing a fine red ruby bestowed good fortune on its owner - although the owner must have already had good fortune enough to possess such a rare and beautiful gemstone!
Many people associate its brilliant crimson colors with passion and love, making ruby an ideal choice for an engagement ring. Ruby is the red variety of the corundum mineral species, while all other colors of corundum are called Sapphire.
This most sought after gemstone is available in a range of red hues, from purplish and bluish red to orangish red. Ruby is readily available in sizes up to 2 carats, but larger sizes can be obtained. However, in its finest quality, any size ruby can be scare. In readily available small sizes, ruby makes an excellent accent gemstone because of its intense, pure red color
Ruby is mined throughout Southeast Asia. While Thailand and Myanmar (Burma) produce exquisite examples of this gemstone that the ancient Sinhalese people called "Ratnaraj," the King of Gemstones.
Despite all the best efforts of gemstone merchants to use technology to enrich color, fine ruby is still exceptionally rare. After being extracted from the earth, rubies today are commonly heated to high temperatures to maximize the purity and intensity of their red hue. Impurities may also dissolve or become less noticeable after heating. However, heating will only improve the color if the gemstone already contains the chemistry required. Occasionally rubies with small imperfections are permeated with a silicate byproduct of the heating process, which helps to make small fissures less visible. This enhancement, like heating, is permanent and rubies, whether enhanced or not, remain among the most durable of gems.
Today a new method of artificially coloring the surface of paler rubies through the diffusion of beryllium, or a similar element, has made the red of ruby more affordable. Although this method is not yet common, in the future beryllium-diffused rubies may offer an affordable alternative to either untreated or heat-enhanced rubies, which are both much more rare. However, recutting or repolishing may affect the color of some beryllium-diffusion treated rubies.    

 

Sapphire 

 

Velvety blue. Liquid blue. Evening-sky blue. Cornflower blue. Sapphire, beloved for centuries as the ultimate blue gemstone. The ancient Persian rulers believed that the earth rested on a giant sapphire and its reflection colored the heavens blue. Indeed, the very name in Latin, "Sapphiru," means blue.
But like the endless colors that appear in the sky, sapphire is also found in many, many other shades besides blue, from the gold of a sunrise, to the fiery reddish-orange of sunset, to the delicate violet of twilight. Sapphire may even resemble the pale white gloaming of an overcast day. These diverse colors are referred to as "fancy" color sapphires.
A gift of a sapphire symbolizes a pledge of trust and loyalty. It is from this tradition that sapphire has long been a popular choice for engagement rings.
One of Nature's most durable gemstones, sapphire shares this quality with its sister, the ruby.
Sapphire is found in many parts of the world, but the most prized sapphires are from Myanmar (Burma), Kashmir and Sri Lanka. The purer the blue of the sapphire, the greater the price the gemstone can command, however, many people find that the darker hues of sapphire can be just as appealing.
Over the centuries, methods have been developed to enhance the purest hues of sapphire. This is now commonly achieved by controlled heating, a technique that not only improves color but also improves clarity. But heating will only improve the color if the gemstone already contains the chemistry required. Heating sapphires is a permanent enhancement, as lasting as the gemstones themselves.
A new method of artificially changing the natural color of a sapphire is diffusion, whereby beryllium or a similar element is diffused into the surface of the gemstone, producing a richer color. Sapphire treated by diffusion is far less costly and much more available than rare fine untreated gems or those successfully heat-treated. Diffused sapphire is available in shades of orange, pinkish orange, yellow and sometimes even blue. Information about diffusion should be provided on the invoice for your jewelry. Recutting or repolishing may affect the color of some diffusion-treated stones.    

 

Topaz 

 

The Egyptians said that topaz was colored with the golden glow of the sun god. Legend has it that topaz dispels all enchantment and helps to improve eyesight. The ancient Greeks believed that it had the power to increase strength and make its wearer invisible in times of emergency. Early discoveries from Brazil in rich reddish cognac colors to vivid pinks, were used to grace the jewelry of the 18th and 19th Century Russian Czarinas, hence earning the moniker of "Imperial Topaz."
Topaz sometimes has the amber gold of fine cognac or the blush of a peach, and all the beautiful warm browns and oranges in between. Some rare and exceptional examples are pale pink to a sherry red.
Topaz is found in Brazil, Mexico, Sri Lanka, Africa and China. The birthstone for November, topaz is a talisman for the sign of Sagittarius and is the suggested gift for the 23rd anniversary.
Blue, once the most rare color of topaz, is today the most common, thanks to a stable enhancement process that turns colorless topaz blue. After the raw topaz is extracted from the earth and cut, it is irradiated to brown and then heated to sky blue. This enhancement process is permanent. Due to the popularity of blue topaz, a new treatment process called vapor deposition has been developed to create additional colors of topaz. In this treatment process, similar to those used by opticians and camera makers to make lens coatings, a thin colored film is bonded on the surface of topaz to create dark blue, red, pink, and green colors or rainbow iridescence. These vapor deposition-enhanced topaz colors must be handled with special care, as the coating can be scratched or abraded.
Topaz is a very hard gemstone, with a Mohs hardness of 8, but it can be split with a single sharp blow, a trait it shares with diamond. As a result it should be protected from hard knocks. Clean with mild dish soap; use a toothbrush to scrub behind the stone where dust can collect.   

 

Tourmaline 

 

For centuries tourmalines have adorned the jewels of royalty. The Empress Dowager Tz'u Hsi, the last empress of China, valued the rich pink colors above all other gemstones. The people of ancient Ceylon called tourmaline "turmali," the Sinhalese word for "more colors." Perhaps this is why ancient mystics believed tourmaline could encourage artistic intuition: it has the palette to express every mood.
Vivid reds, hot pinks, verdant greens and blues abound in this marvelous gem variety. Earth tones as varied as a prairie sunset are readily available. Not only does tourmaline occur in a spectacular range of colors, but it also combines those colors in a single gemstone called "bi-color" or "parti-color" tourmaline. One color combination with a pink center and a green outer rim is called "watermelon" tourmaline, and is cut in thin slices similar to its namesake.
Dark blue, blue-green, and green tourmalines are occasionally heated to lighten their color. Red tourmalines, also known as rubellites, and pink varieties are sometimes heated or irradiated to improve their colors. Heat and irradiation color enhancement of tourmalines is permanent.
Occasionally, some tourmalines may have surface-breaking fissures that are filled with resins, with or without hardeners. Care must be observed with these gemstones. Avoid exposing them to harsh abrasives and strong chemical solvents.   

 

Turquoise 

 

Turquoise is among the oldest known gemstones- it has been mined since 3,200 BC. It graced the necks of Egyptian Pharaohs and adorned the ceremonial dress of early Native Americans. This robin egg blue hued gemstone has been attributed with healing powers, promoting the wearer's status and wealth, protection from evil and brings good luck.
Turquoise is an opaque, light to dark blue or blue-green gem. The finest color is an intense blue. Turquoise may contain narrow veins of other materials either isolated or as a network. They are usually black, brown, or yellowish-brown in color. Known as the matrix, these veins of color are sometimes in the form of an intricate pattern, called a spider web.
To improve its color and durability, turquoise is commonly permeated with plastic, a stable enhancement. It is also sometimes permeated with colorless oil or wax, which is considered not as stable as plastic. Some turquoise is dyed to improve its color, but rarely, as this is an unstable enhancement.
Special care is required for turquoise regardless of whether or not it is enhanced. A porous gemstone, turquoise can absorb anything it touches. Avoid contact with cosmetics, perfumes, skin oil, acids, and other chemicals. Avoid dehydrating it or exposing it to heat.

 

 

 

Color

 

Color is the dominant feature of a colored stone, and thus is considered in the grading process. Color grading is described in terms of hue, tone and saturation. The grading for a gemstone's color is based on the GIA colored stone grading systems. The systems are applicable for color gems that are transparent, and do not apply to opaque gemstones such as pearls, opal, coral, etc. Hue is described as the shade, tint or sensation of a color. Below is 31 basic hues that can be used to describe all colored gemstones.  

 

         

 

 Clarity

 

Inclusions are natural flaws that develop as gemstones form, impacting the clarity of the stones. 

 

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