The World of Diffusion Sapphire Gemstone

Sapphires can be artificially treated in labs in many ways. One of the most prolific technologies to produce these gemstones is lattice diffusion. So let us do a quick review on the lattice diffusion sapphires.

What is lattice diffusion after all?

Lattice diffusion is a commercial gemstone treatment process that involves use of heat and chemical agents to diffuse the ingredients into a gemstone so that it will change colours as per requirement. The best part of using this technology is that gemstones of any colour can be produced. Sapphire gemstone showcasing myriad colours like vibrant red, fiery purple, electrifying blue, silky yellow and pitch dark blacks are produced using diffusion through the crystal structure.

In some cases, sapphire beads are treated with lattice diffusion that can have shallow embeds of colours superficially exhibited on the surface. In others, the colours can penetrate deep into the very core. It all depends on the conditions and impurities already present in the crystal structure that interact with each other randomly during diffusion.

Sapphire Beads

Is lattice diffusion for sapphire legal?

Heat treatment is a legal and accepted technique used on sapphires and rubies. Lattice diffusion however, require regulation from top gem laboratories and trade organizations as far as production and selling are concerned. Lattice diffusion, in no way, adds monetary value to the gemstone. It only improves the brilliance and clarity with a more consistent appearance.

It is legal, and is very different from the process of dyeing and stabilizing. The molecules added to the crystal structure can’t be detected even under the most powerful microscope. Hence, a gemstone dealer has to necessarily produce a certificate labelling the stone with lattice diffusion.

Types of diffusion methods:

Apart from lattice diffusion, certain gemstones are also treated using Surface Diffusion and Pipe or Channel Diffusion.

Surface diffusion:

It is the addition of natural colouring elements like iron, copper, titanium and chromium to the shallow surface of a gemstone during heat treatment.

  • It is sued largely on corundum and silica-based gemstones after cutting is done. 
  • The colour penetration is usually less than 30%.
  • It is done at melting point of the element so that it diffuses evenly into the crystal up to a depth of 1 millimetre.

 

Surface diffusion is done for blue sapphire beads and rubies. Colour obtained on a gemstone using the surface diffusion could be lost due to re-polishing, scratching or resetting.

Blue Sapphire Gemstones


Channel Diffusion:

Also called as pipe diffusion, this heat treatment technique is applicable to feldspar and Labradorite gemstones. It is done using copper as the diffusing element. The diffusion occurs along the channels and can be easily detected under microscope.

Identification of surface and channel diffusion sapphires is done by studying the bands and zones running parallel to the crystal facet.

Unlike the gemstones that are heat treated using chemical dyes and fillers, those produced using lattice diffusion are relatively sturdy and long lasting. They cost a little less than other varieties, but exhibit the same brilliance and clarity. Moreover, they are easier to machine and cut.

Paraiba Tourmaline: The Neon Gems from Amazonia

Tourmaline gemstones and Paraiba are now commercially accepted as synonymous with each other. Considered as an electrifying item for jewellery and fashion, tourmalines bearing this characteristic shade owe their origin to north-eastern parts of Brazil. Much later, the sizzling varieties in effervescent green-blue were mined from Mozambique and Nigeria. If you are planning to buy a Paraiba tourmaline, there are chances that you might get confused between the ones coming from Brazil and those mined from Africa.



How are they different? Does it really count if they are from different sources? How to tell the difference between the two?

In terms of physical differentiation, it is very hard to find the variation between the Paraiba tourmalines from Africa and Brazil. Even under the microscope, they are hard to be differentiated.

Tourmaline gemstones Beads

So, how to differentiate? The only way gem labs can find the difference is by using quantitative chemical testing. Origin-wise, gem collectors rank Brazilian tourmalines higher than the ones mined from Africa. The African tourmalines have a reputation similar to what Burmese rubies enjoy in the gem lines.

History of Paraiba:

One of the recently discovered naturally-occurring gemstones, Paraiba tourmalines have a history dating back to 1980s, when Heitor Dimas Barbosa and his assistants dug out pegmatite deposits in the hilly areas of Paraiba in Brazil.

Why Paraiba gemstones are so popular?

The shady electrifying blue shade in the Paraiba tourmalines matches the beauty of blue sapphires. The blue colour appears due to the presence of copper oxides and hydroxides. Brazilian stones are darker in colour compared to their African counterparts by virtue of higher copper ions in the crystal structure.

Paraiba tourmalines exhibit a variety of colours ranging from sky blue to aquamarine to psychedelic blue. Highest variation in colour shades is observed in Mozambique Paraiba tourmalines.

World’s most famous Paraiba:

The Guinness World Records rank stunning Ethereal Carolna Divine Paraiba as the world’s largest, flawlessly cut naturally occurring Paraiba tourmaline in the world.  It weighs 191.87 carats and is enlisted in the same bracket as Logan Sapphire, Hope Diamond, The Golden Jubilee and Alan Caplan Ruby.
 
The Ethereal Carolina Divine Paraiba is an oval shaped tourmaline featuring Brilliant Cut, and is four times heavier than the second largest tourmaline ever mined. The stone now graces as a part in the necklace called Paraiba Star of Ocean. It entered the ranks in 2009 when the stone featured in the necklace designed by Canadian jewellery house- Kaufmann de Suisse.

blue topaz gemstones

This tourmaline exhibits a radiating neon blue-green colour very distinct from the traditionally mined stones. It is best described as the blue of the tropical ocean. Even the necklace it is fit into has been inspired from the aqua flora and fauna. A compliment to the marine animals like turtles, shells crabs, star fish, rays and sea horses, Paraiba tourmaline is flanked by the likes of canary yellow diamonds, blue, orange sapphires, ruby, garnet, emeralds, Tsavorite and blue topaz gemstones. The 191.87 carat Carolina tourmaline easily exceeds the size of all other gemstones.

Opalescence: The Glorified History of Milky Stones

Searching for real opals? You should be familiar with the characteristic optical features that a natural, untreated opal exhibits. To check the authenticity of the opal, get it under a Turbidity meter. All opals exhibit an optical phenomenon derived from their own primary name- opalescence. It is defined as the milky and turbid appearance in opal.

Opals: The Magic of Milky White

Often referred to as the stone from the Cosmos, opal is a Sanskrit word- Uppal meaning “precious milky stone”. It is a gemstone largely constituted of hydrated silicon di oxide. It is an amorphous stone and is extracted largely from the Southern Hemisphere. In fact, it is actually the National Gemstone of Australia.

The various forms of opal are:

1. Precious Opal
2. Fire Opal
3. Potch Opal
4. Girasol Opal
5. pink Opal Gemstone, also called Peruvian opal

Opals actually exhibit both Play of Colour as well as Opalescence.

Opal gemstone beads


How opalescence occurs in the gemstone?

Opalescence is confined largely to the blue spectrum during reflection of short wavelength light rays. It is because of this phenomenon that a gemstone appears turbid with a shiny blue surface. Another reason, it appears blue is due to the significantly high traces of water, which could be as much as 21% of the silica crystal volume.

The spaces where water is present hinder the passage of light, making the gemstone look milky. Through these spaces, no diffraction occurs. The internal scattering around the water traces render the opal its characteristic opalescence.

Opals that made History:

Opalescence can occur along with white, colourless, yellow, red, grey, black and fiery shades of red and blue as well. Diffraction causes flashes of Play of Colour. Intensity of opalescence decides the brilliance and clarity of the gemstone, and hence commands the price. The red opal beads as well as blue opal beads are extensively used in jewellery.

Opals in flat cabochon glorify the opalescence in the most beautiful way. The most popular opal gemstones in the history of mankind are:

Sun God Opal:

A 16th century gemstone, carved from mines in Mexico. It is a 35 carat Aztec-era stone with a singular quality. It is a dazzling item showcasing opalescence and play of colours brilliantly.

Dark Jubilee Opal:

A thrilling example of Australian opal deposits, this 314.8 carat gemstone was mined from Coober Pedy.

The Olympic Australis:

Named after the Olympic Games in Melbourne, this is one of the purest mega-carat gemstone ever mined. Valued at $2,500,000 (Australian Dollars), it is a massive 17,000 carat opal exhibited all over the world.

The Butterfly Stone:

Also named as the Red Admiral, it is a unique gemstone exhibiting opalescence at only certain angles. It resembles the red English butterflies and hence the name.

Empress of Australia:

Rightly named, this gemstone was mined in 1915. It is referred to as ‘Kaleidoscope Queen’ and ‘Tartan Queen’. It weighed 500 carats in its initial days of glory.

Other prominent opals owned by museums and individual collectors are Pride of Australia, The Flame Queen, The Black Prince and Halley’s Comet.

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How to identify a genuine Aquamarine gemstone

Aquamarine is blue green gemstone cut in variety of shapes. Cabochon, Fancy and Emerald step-cut are popular among the gem cutters, who cater to the demand of the art galleries and collectors from across the world. But are Aquamarines worth the attention they get in the gem market?

Here is how you can find and authenticate a genuine Aquamarine and stay clear from disputes.

1. Heat treatment for colour enhancement:

Aquamarine gemstones are heat treated to enhance the colours and impress the consistency. Many untreated aquamarines are also available in the market, but they exhibit translucency and opacity to a certain degree. High quality Aquamarine gemstones are identified by their lighter shades, which means they may not have been heat treated. The stones heat treated to 450 degrees centigrade are often found to have darker shades, but may not be a high quality beryl.

Aquamarine gemstones beads


Note: Aquamarines heated beyond a specific high temperature lead to irreversible discolouration. Thus the spectrum of authenticity is very small as far as gems heat treatment range is concerned.

2. Is an aquamarine only blue in colour?

Aquamarines fall in the category of clear blue and clear green beryl family. The coloured Aquamarine and Chrysoberyl resemble very closely to each other. The colourless variety is called Goshenite, but is now tagged as colourless beryl.

3. Specific Gravity is higher than other stones:

Aquamarines are heavier than other gems. The stones extracted from Latin American mines have a specific gravity ranging between 2.66 and 2.80. The ones mined from Asia and African mines have higher density due to greater presence of alkali ions.

Gems are immersed in liquids with higher density and the results are noted. Whether the gemstone floats or sinks into the liquid decides the authenticity of Aquamarine.

4. Refractive indices:

Aquamarines beads have a refractive index ranging between 1.572 and 1.590. It exhibits a brilliant and unhindered impression when exposed to white light.The originality of the stone is established by placing it under Refractometer. Here are different optical phenomena observed in the real Aquamarine.

Aquamarines beads

  • Pleochroism:


Aquamarines can exhibit colour dichroism owing to the presence of more than one colouring ions like chromium, iron and copper. The strength of the colour depends on the percentage of the ions. Birefringence can range between 0.005 and 0.008, which represents the saturation of the colour.

  • Iridescence:


Conchoidal fracture in Aquamarine can cause rainbow effect. It is caused due to diffraction combined with interference.

  • The Cat’s Eye effect:


Aquamarine exhibits chatoyancy due to the presence of rutile in the crystal structure. Rutile is composed of titanium dioxide and can be found in traces in gemstone families like quartz, beryl, chrysoberyl, charoite, tourmaline, feldspar, Labradorite, moonstone, apatite and tourmaline.

  • Asterism:


Asterism in Aquamarines is a rare phenomenon, but not an exception. Polished, untreated Aquamarines from Brazil show 4-ray star patterns sparingly.

There are different closely linked beryl gems that can be confused with Aquamarine. Study the colour and the crystal lattice under a microscope for further verification.

Top 4 Gemstones for People Born Under Cancer Sun Sign

If you were born under the sun sign of Cancer, you can choose from plenty of gemstones for you. Cancer people are caring and gentle, and the birthstones identified for this sun sign balances the characteristics traits. These birthstones serve as a lucky charm, and it can help in keeping the emotional serenity under control. You must be aware of the different gemstones for cancer being born between 21st June and 22nd July. Once you have a list, making a choice, as per the suitability will be easier for you.
List Of Cancer Birthstones:

As mentioned, there are lots of lucky birthstones for cancer. In this article, you can take a look at four top stones that you might try.

1.  Emerald:

It is a traditional birthstone of Cancer. Apart from that, it is also the birthstone of the people born in June. In fact, the green variety is the lucky color for all Cancerians. It can help in bringing balance in life. Emerald Gemstone Beads are believed to carry the power of emotional wellbeing for the individual wearer. In addition to that, if you wear this stone, it can bring in clairvoyance, a talent which is unthinkable of many men and women of this sun sign.

Emerald Gemstone Beads


2.  Pearl:

This is the ideal birthstone in terms of both western and Vedic astrology. Unlike other gemstones, this cancer stone is not a geological effect, but marine activities that take place inside the shells. The shiny and round Pearl Gemstone Beads are lucky, and is said to strengthen relationships and marriages. In addition to that, it can even keep your children safe from any kinds of threats or dangers.

3.  Moonstone:

This is again a well known birthstone of Cancer in terms of astrology. It is the ideal birthstone for the month of June. The opalescent variety is the most suitable stone for Cancer, and you will benefit from it by wearing it. In fact, there are several ancient beliefs pertaining to Moonstone Beads, where the stone was solidified by the rays of the moon. Moon is the ruling planet of the cancer, and hence moonstone is the planetary stone. It can cure anxiety and even stimulate clairvoyance. Often, it is also said to act as the stone of security.

4.  Ruby:

Ruby is the traditional stone associated with this sun sign. It can focus on the energies of the planet and bring in positive vibes. Apart from that, the stone can bring vitality, strength, courage and confidence. It can be used to enhance energy and bring in success. Happiness and joy are also associated with this stone. Ruby Gemstone Beads are also known to have several healing properties. Therefore, it is effective for healing blood and infection while increasing the positive thoughts and patterns in the wearer.

Ruby Gemstone Beads


Now that you know the 4 most important birthstones for Cancer, you can definitely try out the one that suits you the best. In this context, you can also talk to an astrologer and get the necessary recommendations on the same.

 

A look at top 8 Affordable & Best Semi-Precious Gemstones

Gemstones are not only worn for astrological purposes, but many are passionate about wearing them as jewelries. However, despite loving them, you might not be able to buy them because of their costs. It is true that most gemstones are so expensive that it is often out of your reach to buy them. At the same time, you will also be happy to know that many gemstones are affordable and they are classified under the category of semi-precious gemstones. It goes without saying that precious gems like Ruby, Diamond, sapphire and emerald are expensive. Some semi-precious stones are rarely available, and they are also expensive. Apart from that, the other semi-precious gems are affordable.

Most Affordable & Best Semi-Precious Stones:

Below is a list of some of the most affordable semi-precious stones that you can add to your bucket.

semi-precious stones

1.  Tiger’s eye:

Most people are familiar with this stone because these are very common and easily available. Brown in color, it comprises of a silky luster, and it is affordable. Yellow and black are the most common varieties of this stone, and it is available at only few dollars per carat. However, some of the rarest varieties can be expensive.

2.  Rose quartz:

Many types of Rose quartz are currently available and they are affordable, as well. Rose quartz is highly popular, available in pale pinkish hue. It can look wonderful in any jewelry. It is even popular for healing and therapies.

3.  Amethyst:

A type of quartz, this stone comes in a purple color. The color can range from lavender to deep violet. Amethyst Gemstone Beads were once expensive because it was rare. However, now it is commonly available and is cheap. 

Amethyst Gemstone Beads

4.  Agate:

You can expect to find many types of agate in the market. These include blue band agate, fire agate, blue lace agate, moss agate, pink agate and others. Some of these are rarely available and hence expensive than the others. However, most of these are affordable because of their easy availability. 

5.  Citrine:

The gemstone is usually amethyst or quartz. When it acquires heat treatment, it turns into yellowish brown color and is known as citrine. Since it is easy to manufacture Citrine Gemstone Beads in lab, they are highly affordable and popular.   

6.  Jasper:

This stone can come in variation of colors, and red is the most common type. It appears red because of the iron inclusions. Most of these stones sell out at a very cheap rate, and it can be highly suitable when used as a pendant. Its soft nature makes it unsuitable to be used in rings.

7.  Onyx:

The easily available stone is popular and affordable. True black onyx often sells at few dollars per carat. Some stones might contain bands of white though in most cases, it is pure black. Black onyx is used for its mystic powers, and it is used for many other reasons.

8.  Turquoise:

The mixture of both copper and aluminum makes it look appealing. The Turquoise gemstone is often treated for color enhancement, and treatment reduces the prices of the stone.

Top 5 Gemstones for People Born Under Scorpio Zodiac Sign

Scorpio is the most emotional of all zodiac signs, and several birthstones have been associated with this zodiac. The different birthstone act as lucky stones or charms and they can absorb the negative energy, thereby promoting positive energy. People, who are born between October 24 to November 21st come under this sun sign. Pluto is the ruling planet, and its position in the birth planet can create a great impact on the character and relationship of a person. The main birthstone of Scorpio is Topaz, but there are many more other stones associated with this sun sign. Let us take a look at 5 Gemstones for people born under Scorpio Zodiac Sign:

1.  Topaz:

Scorpio is considered to be the most powerful of all zodiac signs, and it can create a dual impact. Therefore, a scorpion individual requires Topaz for creating an inspiring and stimulating influence on both the mind, and the soul. Topaz gemstone beads conduct the energies of the ruling planet, Pluto. It plays a great role in enhancing the area of relationship with loyalty, constancy and faithfulness. It is important to note that the strong influence of Topaz can create a balancing effect on the nervous system and the chakras. Apart from that, it can even heal health issues like gout, asthma problems, mental issues, sleeping disorders, etc.

2.  Aquamarine:

It is the traditional birthstone of Scorpio according to the old Arabic, polish, Hebrew and Roman calendar. The Aquamarine Gemstone variety of this stone can bestow some of the best foresight to the wearer. In addition to that, it is even to known to relieve stress and anxiety, thereby stimulating youthful joy and happiness.
Aquamarine Gemstones 3.  Opal:

Opal is one of the amazing gemstones that work for Scorpio people. It is ruled by Pluto. The stone is mystic, healer and artist. Moreover, this stone is also known for offering its support during times of transition and intense change.  

4.  Beryl:

This stone belongs to a group of minerals, which even include aquamarine. In the old Italian and Russian calendar, this was the birthstone of October. The precious stone can be found in wide varieties of colors except green. The green one is known as emerald. The stone can bring joy and cheerfulness in a solemn and serious Scorpion. In addition to that, it can even enrich the power of love and marriage. Yellow colored beryl is the most suitable color for people belonging to Scorpio zodiac, and it deepens the level of sincerity in a person.

5.  Tourmaline:

Also known as Rubellite is often associated with Scorpio. It influences a person with positive energy. Moreover, it might even strengthen blood, thereby providing complete balance to the structures of blood vessels and veins. This in turn promotes blood circulation. The Tourmaline Beads can even heal the nervous system, especially in people born to a Scorpio sun sign.

Tourmaline Beads

Apart from these five there are several other gemstones that contemporary astrologers describe as the birthstone of Scorpio. You need to find out what suits you the best, and which of them proves to be lucky for you. On the basis of that, you can make your decision.     

Most Exclusive Gemstones Ever Mined: The Rarest of the Rare

Considered as the tears of the angels, gemstones are one of the most fascinating creations in the Universe. The oldest known gemstone treasury belonged to Egyptian queen Cleopatra, and today one of the world’s largest gemstone collections belongs to Queen of England, something worth over $80 million. Diamonds, emerald and rubies are quintessentially the top gems known for their rare beauty. However, there are some paltry crystals that rank higher than the commonly known gems.

Painite

The name Painite commemorates the person who discovered the stone- Arthur C.D. Pain.Already listed in the Guinness World Recordsas the rarest gem mineral not just on Earth but also in the Universe, Painite is the costliest known naturally occurring material. A carat costs anywhere between $18000 and $50000, meaning you can buy at least a dozen rubies at the cost of one 1-carat Painite. 

How it looks like

Painite is a dark red gemstone showcasing varied hues when viewed from different angles. It also shows a distinct green colour under UV. Mogok in Myanmar is the only known site of extraction for Painite. The major constituents of Painites are calcium, zirconium, boron, aluminium, chromium and vanadium. 

Fact: 

Painite exhibited at the Tucson Gem & Mineral Show, Arizona was tagged at $60,000 per carat.

Bixbite

More popularly called as the Red Beryl, Bixbite was first discovered by renowned gem collector Maynard Bixby. Mined from the Wah Wah Mountains in Utah, the price of 1-carat Bixbite is $12000. The most popular bixbite is the Ruby Violet Claims which is currently priced at $10 million. 

Bixbite is found only in Utah, but some gem researchers also discovered pezzottaite in Madagascar and Afghanistan which resemble these costly gems.

Fact:

Bixbite is a red beryl. However, gem buyers often confuse the gem with bixbyite which is a black coloured manganese iron oxide mineral. The names however have been attributed to the same person who discovered the gemstones. 

Serendibite

Found sparingly in Sri Lanka, Serendibite is a greenish blue coloured gemstone. The name is derived from Arabic word for Sri Lanka- “Serendib”.  It has an opaque appearance and exhibits pleochroism in golden brown, green and blue under diffused low wavelength light.

1-carat Serendibite can cost up to $15000 owing to the rarity. It features a very rare composition of calcium, magnesium, aluminium, iron, boron and silicon. It is 100% inert to UV fluorescent light making it all the more difficult to identify. 

Fact: 

Serendibite is used exclusively for black gemstone jewellery.

 

Poudretteite

Officially named after the Poudrette family, this gemstone belongs to the crystal group of cyclo-silicates. First discovered in Quebec, Canada Poudretteite is a relatively soft gemstone (Mohs hardness- 5.0) bearing pink and violet shades with prismatic hexagonal cuts. Mogok valley is the largest producer of Poudrettite.

We can only speculate about its price.As per gem auction tags, it is usually priced from $2000 to $10 million per carat.

Fact: 

A 9-carat Poudretteite remains the heaviest gemstone ever mined.

 

Pure Science: Common Pearl Treatments that Turn Them Alive

In a world driven by the love for diamond and ruby beads, garnets, the pearls have a place of reverence in the gemstone market. Revered for their clarity and pristine beauty, since time immemorial, pearls have always been an item of great respect. From finding a place in God’s necklace to shining majestically atop the crowns of most powerful rulers, there is a story behind every pearl. After all, pearls are one of the few known organic gemstones found exclusively on the planet.

Not all naturally produced pearls have the signature lustre and translucency. Most pearls require an additional treatment to derive the clear appearance. 

Here is what you should know about pearl treatments in a highly competitive industry.

Accepted commercial pearl treatments 

 

Polishing is a world-renowned process done to improve the lustre of the pearls. It has been established as an accepted process since many centuries, much before the technology to dye and heat up the pearls were discovered.

The common treatment used in pearl manufacturing and marketing industry are:

Irradiation 

Bleaching and dyeing

Heating

Waxing 

Filling and working

Drilling

Cutting

Any treatment is engaged in pearl manufacturing only after ensuring its credibility in alleviating the aesthetic and economical value of the item. All pearls are anyhow polished and cleaned off the organic debris before setting up for sale in the market.

For a lustrous shine, a pearl is subjected to following treatments.

Dyeing

Pearls are subjected to a solution of silver nitrate and oils. They give the pearl gemstones a more uniform shade. The use of silver nitrate works in the same way as in the development of a photographic film in dark room. The pearl gets a rich metallic sheen with a blackish shade. Over a period of time, the effect of dyeing fades away.

Irradiation

It is done using powerful gamma radiations on Akoya pearls. Since it involves use of radiation, only certified pearl treatment units are allowed to carry out the process legitimately. 

The irradiation produces a more consistent appearance, with iridescence conspicuously visible on the surface. Unlike dyeing, irradiation of pearl gives a long lasting effect.

Maeshori

Though a Japanese term, this treatment has found its way into freshwater pearl and Tahitian pearl manufacturing. The process involves systematic heating and subsequent cooling of the pearl to tighten up the nacre. It is more of a makeover or a facelift for the pearls, deriving a rather long-lasting lustre without the involvement of any chemical agent.

Treatment traces in the market

Some pearls can lose their sheen by the time they reach the market. Some of them may even lose it after buying! As a pearl lover, you must verify the authenticity of the pearls beforehand by checking out the nature of treatment done during processing. 

From concentration to consistency, an artificially enhanced pearl is hard to detect unless tagged correctly by the manufacturer. The only way to find out the true story of pearl treatment after processing is to do a destructive test! And it is a very expensive test to perform.

Finishing Methods in the Creation of Magical Pearls

Pearl is one of the oldest known gemstone. Along with amber, corals, jets and ivory, pearl is the only known organic gemstone that retains its place in the list of precious items in the world. Ivory and coral have witnessed a reasonable decrease in market share, considering the environmental regulations imposed on their extractions. However, as pearls make a wave of adulation across world, there are some critical points you should know while buying them, especially related to their culture, surface finishing, and commercial selling.

Pearl farming

Also called as pearl culture, pearl farming is a technology-driven science today. Cultured pearls are grown in controlled biological conditions using different varieties of molluscs. Depending on the family of bivalve molluscs, there are different varieties of pearls.

The pearl oysters used on pearl farming are:

Freshwater mussels 

Marine pearl oysters

It is worth noting the fact that all shelled molluscs are known to produce “pearl” material in some form or the other. It is only the nacre secretion that gives the pearl its signature lustre and value.

Pearl finishing

Due to the reduced term of pearl culture, the quality has significantly dropped. Thus, it calls for finishing process that give the pearls their iconic lustre, reflection .refraction and diffraction properties. The degree of translucency heavily depends on the precision of finishing process. 

Here are some of the accepted finishing treatments done on nacre pearls.

Polishing 

It is a common treatment done on pearls coming from South China Sea. The pearl is tumbled in concentrated brine solution, which removes the layers of mucus and tissues over the surface. Polishing is also done by bleaching the surface to make them appear brighter. 

Polished pearls are available in cream, light pink and yellow-brown shades. Unlike natural pearls, polished pearls show better results when polished with abrasive solutions.

Maeshori

Ever heard of heat treatment on pearls? Yes, Maeshori is a unique Oriental pearl treatment that involves dipping of the Akoya pearls in a methanol solution. It effectively removes all impurities on the surface and also gives it a naturally brighter appearance, resembling the natural ones. 

As far as duration of soaking is concerned, a pearl can be dipped in the alcohol solution for as long as 45 days! The treatment not only removes the impurity, but also heals the pearl of its flaws, cracks and roughness. 

Bleaching 

A rather corrosive pearl treatment, this is done only to give the surface a more uniform appearance. It is applicable to pearls with thin nacre shell. Pearls with thick nacre are kept away from this processing. 

Buffing

Often done to remove visible scratches on the surface, buffing with beeswax and chemical agents is a wasteful method that penetrates deep into the nacre. It is recommended only for minor scratches. 

Lacquer coating 

Pearls with light lustre are coated with lacquer to improve brilliance. It is a temporary treatment that often wears out. Commercial pearls are coated with silicone polymer coatings, but it not a widely accepted treatment. 

In a nutshell, the cost of pearls drop significantly if there is any visible sign of surface finishing. That’s why natural pearls command a higher price in the market.