World’s Least Heard Gemstones that Still Cost a Million

Wouldn’t you love to own something that can never be replicated or flaunted by anyone other? Here is your chance to actually own something that is not only rare but also rated among the least known gemstones in the world.

Grandidierite:

Discovered in 1902, this gemstone is named after French naturalist and explorer, Alfred Grandidier. After 114 years of oblivion, grandidierite was first brought to limelight in 2015! Best quality gemstones are mined from Madagascar and Sri Lanka. A neo-silicate, it is relatively hard ranking 7.5 on Mohs scale. It has a typical bluish green colour with translucent appearance and fine rutile network.

Gemstone Beads


Jeremejevite:

First discovered atop Mount Soktui in Siberia and Lake Baikal, Jeremejevite is found in small traces along with albite, tourmaline, and quartz. Other than Siberia, gem collectors have excavated the rare crystals in Namibia and Germany. It is a colourless gemstone with faint yellow and blue colour. Worth at $18000 per carat, Jeremejevite is linked to other rare mineral gemstones like Hulsite, Fluoborite and Sakhaite.

Taaffeite:

Named after Richard Taaffe, Taaffeite is an oxide mineral bearing greyish blue and red greenish shades. A very hard gemstone ranking 8.5 on Mohs scale, this gemstone is mined from the renowned mines of Ratnapura in Sri Lanka. Price tags hover around $5000 per carat, finding a Taaffeite is very rare. Spinel varieties are falsely sold off as this rare gemstone.

Musgravite:

Musgravite exhibits red, mauve, blue, violet and grey colours.Rich in magnesium impurities crystallised within beryllium oxide in a trigonal system, it is closely linked to Taaffeite but was discovered at least four decades later in the mines located in Musgrave Range in South Australia. 1-carat Musgravite can fetch a price of $35,000 and more. In 2015, only eight recognised varieties of the gemstones were reported to have been extracted for commercial purpose.

Red Diamonds:

Now we finally have a gemstone that everybody would love to adorn. But the price tag keeps it safe from the crowd! At $8.2 million per carat, red diamonds are not just the costliest gemstones but also the most alluring ones to feature in the list. Unlike other diamond varieties that have boron and nitrogen impurities, the red diamonds are pure in their composition. They are formed out of plastic deformation, which itself is a very rare phenomenon on Earth.

Famous red diamonds to be ever cut by mankind is the 5.11 carat Moussaieff Red, which was earlier called the Red Shield Diamond.  Another celebrity name in the list of red diamonds is the 0.95 carat brilliant cut, round Brazilian Hancock Red which was sold off for a mammoth $880,000 ($926,000 per carat)!

Scapolite gemstone


Scapolite:

It is definitely the one that only a handful of gem collectors actually know, and have seen in reality. Scapolite gemstone displays a fascinating play of colour along with fluorescence and Cat’s Eye effect. It is cut in cabochon to create exceptionally brilliant stone for jewellery. Popular varieties are Lavendar’s Cat eye and purple Tanzanian scapolite with per carat price of over $3000.

Black Gemstones You Never Knew Existed!

Considered as the powerful shadows of the brilliant coloured gemstones, the Black Stones are no longer kept in oblivion. Much like their colourful siblings, black gemstones too have a respectable fan-following. There are many black gemstones used in jewellery and healing, but we present you a list of those featuring in almost every charmer’s wish list.

Black Gemstones


Black Diamond;

Heard about the 33.75-carat Amsterdam Diamond? Or the 312-odd carat the Spirit of de Grisogon! These are black gems.

Diamonds are available in almost every colour known to mankind. And yes, black is one of them. Though rare, black diamonds actually look like the other allotrope of carbon, the graphite. Black diamonds are actually called “Carbonado” and are tougher than the regular diamonds! It consists of traces of diamond, graphite and non-crystalline carbon.

Most geologists believe that carbonado diamonds are actually extra-terrestrialin nature dating back to 3.8 million years of space travel.For instance, Carbonado do Sergio has a meteoritic origin.

Black Opal:

A fascinating variety of opal, Black Opals earned so much popularity that New South Wales- Australia proclaimed it as the official state gemstone! NSW is the world’s largest producer of Black Opals. Due to the small traces of iron oxide and amorphous carbon, some opals exhibit a unique trail of black. Black Opal set in bezel ring is considered as a protection from the evil forces.


The Halley's Comet Opal, a 1982-carat Black Opal is world’s largest uncut gemstone, priced at $1.2 million.

Black Beryl:

Beryl is pretty common in nature, but when they appear in black forms they enter the list of rare gemstones. The black shade appears due to the insertion of microscopic black spinel impurities. They often appear as elongated prisms turning the transparent and clear beryl into greyish. The black opals are distinctly identified by their asterism effect, found in cabochon cuts.

Black Sapphire:

Sapphire is a legendary gemstone particularly recognised from its electrifying blue colour. But the black varieties are even more spectacular in their appearance. Symbolised as the stone of wisdom and confidence, Black Sapphire contains significant amount of aluminium oxide arranged in prismatic tubular and rhombohedral crystalline structure giving them their conspicuous star-shaped optical effect.

Black Sapphires are very well received in the Arabia and Roman culture as an embodiment of fertility and love.

Black Star of Queensland is a 733-carat black star-sapphire discovered accidentally in 1960 in Queensland, Australia.

Black Garnet:

Also known as Black Andradite, it is absolutely hard to imagine that a flourishing red gemstone will also appear in a metamorphic form in black colour! The black garnets are actually a combination of three distinct crystalline structures- pyrope, andradite and melanite. A deeply spiritual gemstone, Black Garnet exhibits clairvoyant properties and heals the negative energy circles.

Other prominent black gemstones in the family that are equally sparkling and popular are Black Obsidian, Smokey Quartz, Black Tourmaline, Onyx and Serendibite.

So next time you shop for gemstones, don’t forget to pay special attention to the black family.

Top 5 Timeless Gemstones That Makes a Great Choice for Every Occasion

The popularity of gemstones depends on a lot of factors. Sometimes it is based on the latest trend or what blends smartly with the season and occasion. Sometimes it is inspired by what the celebrities wore in movies, red carpets, and page three events. Fashion trend keeps on changing but here we are going to reveal Top 5 timeless gemstones that come up as a great choice for every occasion. 

1 Diamond:

Undoubtedly, the list begins with the most beautiful and precious gemstone on the earth – Diamonds. It is a piece of rock that every girl loves. It is said that girls love the diamond, propose her with a diamond she will be in love with you forever. The magnificent colorless stone dazzles, glitters and shines. It comes in an array of colors like yellow, red and blue etc. If you don’t want to go for color diamond then surely the colorless is diamond is what you are going to love. Diamond studded ring comes up as the best option to propose your sweetheart for the wedding. Well, it’s not important that you should wait for marriage to wear diamonds. Wear diamond studded rings, necklaces and earrings and be a center of attraction of every party. 

2 Ruby:

Selecting the second best gemstone in our list was tough. There was a close fight between sapphire and ruby, but ruby gemstone manages to get the second spot in our list of most precious gemstones. The vibrant color of Ruby instantly attracts eyeballs. Ruby gemstone beads are widely used in jewellery as an alternative to expensive diamond. If you want to propose your girl then you can go do with a breathtakingly beautiful ruby studded ring as the gemstone represents love and passion. Well, rubies also come up as a wonderful 15th, 18th and 40th wedding anniversary gift. 

Ruby gemstone beads

 3 Sapphire:

Sapphire gemstone makes the third position in our list of ever popular gemstones. The stone comes in an array of natural shades like green, pink, gray, purple, black and multicolored. The most popular shade in Sapphire remains blue. The shade is even a favorite of celebrities like Kate Middletown. The beautiful Duchess of Cambridge wore a sapphire engagement ring. Well, what makes it interesting is the fact that it was the same ring worn by her mother-in-law, late Princess Diana. Sapphire is a gemstone that depicts royalty. Believe us, a girl is going to love a sapphire studded ring. 

Sapphire gemstone

4    Emerald Gemstones:

The rich dark green stone has been a favorite of royals. Kings and queens loved to wear emerald studded jewelries. The attractive stone is considered to be perfect for every occasion. Moreover, it is considered to be very auspicious for newlywed couples.  Emerald gemstone brings love, passion and commitment in the life of couples. Here is something very interesting for you guys – John F Kennedy proposed his sweetheart Jane with an emerald studded ring.  The stone is also known to have superb healing properties. It helps the wear to come out of depression and anxiety. It improves concentration. The stone is also known to keep the wearer away from heart-related ailments.    
 

 Emerald gemstone

Top 4 All Time Popular Engagement Rings Of Celebrities

The timeless diamonds comes up the classy choice for an engagement ring but colored gemstones are not far behind. The colored gemstones are very much in trend with couples looking for something beyond the diamond. These sparkling gemstones imitating colorful lights come up a favorite of celebrities. Let us take a look at some of the famous colored gemstones engagement ring of famous celebrities.   

1    Kate Middleton:

The gorgeous Kate Middleton’s engagement ring is considered to be the most famous ring of the century. The fact that it was the same engagement ring worn by Princesses Diana makes it really unique. It comes up as a marvelous example of royalty transferred to another. The 18-cart stunning ring with diamond and sapphire gemstone beads was purchased by Prince Charles in 1981. The rings value has increased significantly over the years. Today it is valued at a whopping million dollar. Well, the price is not that makes this ring famous but the emotions and beautiful memories attached to it. It was an emotional moment when Prince William proposed Kate with his mother’s ring. 

sapphire gemstone beads

2    Napoleon Engagement Ring to sweetheart Josephine: 

The ring Napoleon gave to his beloved wife as an engagement ring is counted among top popular colored gemstone rings of all the time. Although the ring was not that expensive because Napoleon was facing financial problems at that time, but the ring was a sure shot stunner. The ring had a diamond and sapphire in tear shaped cut. It was placed in such a way that it represented Man & Woman. The unique setting was called “You & Me”. The magnificent ring was auctioned in 2013. If you are looking for a unique colored ring as engagement ring then don’t forget to take a look at this ring. It surely has the charisma to make you fall in love with it in the very fast look. 

3    Jackie Kennedy

John F Kennedy was known for his great taste. When he decided to propose beautiful Jacqueline Bouvier back in 1953, he wanted the best ring. He met the most famous jewelry designer of that time Van Cleef & Arpels. He designed an eye catching ring with 2 karat emerald. The ring cost Kennedy a million dollar at that time but surely it was worth the price. The design was the highlight of the ring which makes it standout. The combination of diamond accents, emerald gemstone and baguette make it a fascinating engagement ring. 

emerald gemstone

4    Jessica Simpson:

Eric Johnson and the famous actress Jessica Simpson got engaged in the year 2010. The Eric Johnson was looking for a marvelous ring that will make the actress and singer fall in love with the engagement ring. His search for a unique designer for the job ended with Neil Lane, a renowned jewelry designer. Neil designed a marvelous 5-carat ring that had a magnificent ruby in the center and had two diamonds on each side. Eric Johnson’s hard work paid, Jessica simply loved the amazing ring. What made it even more special is the fact that ruby gemstone is her birthstone.  

ruby gemstone

A Look Into Heat Treatments Of Rubies & Sapphire Gemstone

Rubies and sapphire gemstone available in the market are available in two forms. One category would be heat treated with additives, and another would be those without additives. It is obvious that though heat treatment is done to improve the colour of the gemstones, adding extraneous stuff to the crystal structure actually means that there has been physical distortion with the original gemstone. In short, gemstone that has been heat treated with additives is what you should stay away from.

Let us review how heat treatments with and without additives work, and why they are important in gem studies.

Heat Treatments without additives

Natural gemstones command higher price than those manufactured artificially. Natural stones may not be perfect in terms of their brilliance and crystalline structure, but their origin is all that matters. Gems created in labs have lower value primarily because they may not give the same healing benefits that they are known for. 

Heat treated rubies beads and sapphires are common, and they are respected for their consistency and suitability in different applications. They are heated under specific temperatures, glazed in condition that is free from impurities of any kind. Depending on the amount of oxides and the colour-bearing properties, rubies and sapphires exhibit the same beauty as their natural counterparts.

ruby gemstone beads

It is important to note that sapphires and rubies are heat treated using different agents. Heat treatment for sapphire gems is carried out in reducing process, while rubies are heat treated in an oxidizing environment. 

Heat Treatment with additives

The heat treatment process using additives is not illegal, but it affects the commercial viability of a gemstone. All gems have to be necessarily subjected to inspection by leading gem quality testing labs, and this is where additives are named.

The most popular gemstone treatment processes using additives for rubies and sapphire are:

- Lead Filling

Also called fracture filling, this process is utilised to cover up the fissures and cracks. Rubies and sapphires with dull and rough appearance are infused with lead to produce high refractive indices. It can be used for opaque gems as well, which after lead filling result in brilliant transparent or translucent/ milky stones. 

Cheap rubies are available in the market, and they are more often than not, lead filled. Moreover, this additive process is actually reversible. Lead filling for gemstone has been rendered as hazardous, as lead is a carcinogen.

- Recrystallization

In order to enhance the transparency and improve the refractive index, rubies and sapphires are made to undergo recrystallization. The first known synthetic ruby was actually produced using this process. Geneva Ruby in 1886 made headlines, but it turned out to be a reconstructed gem. Same process is used to produce emeralds. 

- Beryllium Treatment 

An accidental discovery led to the commercialization of this process. Between 2000 and 2006, the market was full of richly coloured padparadscha sapphires. Lab testing proved that they were actually orange sapphires, diffused with beryllium ions. Even in natural stones, sapphires have been found to contain significant amount of beryllium impurities. 

 

How To Identify The Treated And Untreated Sapphire Gemstones

In gemstone market, it is very hard to find an untreated piece because of the lack of interest from the buyers. Untreated sapphire gemstone is often mistakenly referred to as natural. The treatment process has nothing to do with the origin of the gemstone in any way. Lapidary units create eloquent sapphire gemstones using elaborate treatments. 

Sapphire Gemstones

Let us find the real differences between the two families. 

Untreated gemstone

The stone that has been developed from the ground and never cut or polished in any way in a lab is labelled as ‘natural’. When the natural stone is not subjected to any chemical or heat treatment, it qualifies as an untreated gemstone. 

Heat treatment, optical irradiation and chemical treatments are done on various gemstones to achieve brilliant colours, clarity and some times better refractive index. Sometimes, a treated natural gemstone is easier to cut and polish than the untreated ones due to better clarity and machining properties.

What happens in gemstone treatment process?

All stones available in the market are subjected to treatments in some form or the other. Heat treatment process changes the colour and clarity. It is during this process that additives and glue are added to fill cavities, fractures and cracks. 

How to identify a pure gemstone?

Gemstone buyers should know certain tell-tale signs to identify 100% pure and natural stones. Regardless of the tag, here are some of the signs you can check to verify the claim of authenticity.

1. Naked eye test 

A true natural stone will reflect light and exhibit lustre. There are many stones that have a dull, waxy and shiny surface. There are some with greasy and silky appearance. High quality stones will reveal rings, stepped granules, splinters and sometimes clear waves inside them. Any polarised chipping in the stone highlights its synthetic origin.

2. Hardness and clarity

Most gemstones have hardness close to diamond. They can’t be scratched or cracked easily. Artificial gemstones, bordering at being fake, are created in the lab and resemble glass. A gemstone from natural treated family will have pure clarity and no cracks. In case of fake artificially treated stones, you can clearly see speckles and minute cracks within the structure arising due to intense heat and pressure

3. Density 

Original stones even after heat treatment will retain their density. Synthetic stones that are subjected to heat treatment gain a few points and actual weigh heavier than the natural stones. This is how lapidary and stone collectors verify Blue sapphire gemstone.

4. Crystal layers

Most gemstones from the natural deposits have a parallel layer running inside the surface. This is what gives the stone its saturation and intensity. For warm coloured stones, look for brown tinge. Reject the stone if you see even the dullest shade of greyness.

The colouring dyes and reinforcing agents diffuse completely throughout the crystal structure uniformly. Some heat treatments produce dramatically altered gemstones that not only look brilliant but also compound the original hardness.

 

Aquamarine: Finding the gems that will give you rewards

Aquamarine is an iconic gem belonging to the same family that also features Green Emerald. Officially ranked as the birthstone for those born in March, Aquamarine gemstone has a glassy lustre and a sea-water hue. But are you aware that there are thousands of duplicate gemstone items that flood the market each year, and remain untraced. So how should one find and buy authentic Aquamarine.

Aquamarine Beads

Here’s what you should do.

Research about famous Aquamarine:

Aquamarines are found as large stones that need cutting and polishing. Most of the naturally mined gems are either opaque or too dull to be used for profitable application. You must do a little research on the world famous Aquamarines.

Dom Pedro:  Officially, Dom Pedro is the largest single piece cut-gem Aquamarine and falls in the category of rarest of rare natural items ever mined from the Earth’s crust. Named after the first two Brazilian emperors, Dom Pedro now stands as 14 inches in the shape of obelisk. It was cut from its 23.25 inches glory by gem artist Bernd Munsteiner.

The Hirsch: It is a 109.02 carat gemstone featuring an emerald-cut. It was one of the first non-treated gemstone to be exhibited all over the world. It was set in 18k gold bracket and diamonds by French Emperor Louis XV.

The Schlumberger Bow: Currently ownedby the Field Museumof Natural History- Chicago, “The Schlumberger Bow” is set in platinum and gold pin along with diamonds. It is a 148.5 carat aquamarine designed for Tiffany. It was first exhibited in the year 1893.

Roosevelt Aquamarine: Gifted to First Lady of USA, Mrs. Eleanor Roosevelt in 1935, the gemstone is one of the largest naturally extracted aquamarines to be ever mined. It weighs 1847 carat. It was cut from a 1.3 kilogram stone of which a single 835 carat aquamarine was gifted to the Maharaja of Kapurthala.

The leading suppliers of aquamarine gemstone beads are Australia, China, India, Kenya, Madagascar, Mozambique, Namibia, Nigeria, Pakistan, Zambia and Zimbabwe. Radiant gems still come from Santa Maria mines in Brazil. So it is not all about the volume, but also about the position Brazil commands in Aquamarine gem market.

Aquamarine Gemstone Beads


How to identify the originality:

# Aquamarine Colour

Aquamarine can exhibit multiple shades of blue, variedly or consistently. It all depends on the amount of chromium and iron ions in the crystal lattice. The popular shades are light blue, deep blue,blue-green and green-blue. The cost of aquamarines isdecided on the basis of the shade saturation and consistency.

# Aquamarine Clarity/Lustre

Deep blue shades are costlier, only if they have a lustrous, crystal clear appearance. Some gems however can have rods running parallel seen like veins and inclusions. Aquamarine can show multiple optical characteristics like chatoyancy and asterism.


# Aquamarine Cut and Shape

Aquamarine gems are cut in cabochon, but faceted cuts also hold significant place in collections. They are perfect for emerald cuts and square cuts. Emerald step-cut and Fancy Cuts are hard to manage, but they are popular among aristocrats as they were before World War II.

Is it safe to wear irradiated Gemstones

It is true that even the most naturally obtained gemstones have to be exposed to some kind of radiation to make them look super cool. This process is called Irradiation and it is done by bombarding a stream of gamma rays at the crystal structure of the gemstone. It indeed makes the gems radioactive. Let us find out if the irradiated gemstones are anyway harmful to the consumers.

Which stones are irradiated?

Topaz is the most commonly irradiated gemstone. Blue topaz gemstone is one of the rarest gems, and is often manufactured synthetically. Nearly 28 million carats (which is roughly 6000 kilograms) of topaz are irradiated each year, globally. USA leads the source, followed by Germany, Poland and Thailand.

Other gemstones usually found in their irradiated states are yellow, blue, green and pink diamond gemstone. Quartz and amethyst beads are also exposed to radiation at some point of time in their life cycle. Goshenite, golden beryl and Heliodor are popular beryls available exclusively in irradiated states. Black pearls extracted after 1970, are either dyed or are irradiated to look stunning.

amethyst beads

So with so many precious gemstones exposed to radiation, it is obvious that consumers need to know to what extent they are susceptible to any hazard.

Is there any way gemstones are regulated in the market?

Yes. All irradiated gemstones have to be necessarily given a certificate from the regulating agencies in the respective countries. All gem producing and gem treatment nations have strict regulations to monitor the radioactivity levels in the irradiated gemstones, whether natural or artificial.


Here are some precious and semi-precious gemstones that have been ranked among radioactive items.

  • Adularia
  • Afghanite
  • Ajoite
  • Amazonite
  • Betafite
  • Boleite
  • Charoite
  • Eudialyte
  • Francevillite
  • Londonite
  • Polycrase
  • Sugilite
  • Thorite
  • Titanite


Despite their radioactive state, they are deemed safe for use on a daily basis.

semi-precious gemstones



Who testifies for irradiated gemstones in the market?

Irradiation is a very commercial process for manufacturing gemstones. The finished items have to be approved by Federal Trade Commission. Other prominent professional organizations are American Gem Trade Association, The World Jewellery Confederation and International Coloured Gemstone Association.

How to tell ifthe gemstone is irradiated?

A gemstone seller can’t sell irradiated items without necessary certification. One of the most recognised certification comes from United States Nuclear Regulatory Commission. Physically, it is very difficult for even the experts to tell whether the gem has been irradiated naturally, or in a reactor or in an accelerator. The certificate, followed by a testing with survey meter is the only way any lay person can adjudge the gemstones as irradiated or not.

Are they safe for daily wear?

Yes. The irradiated gemstones belong to the family of birthstones, and the customer is required to wear it daily for effective healing and metaphysical benefits. Irradiated gemstones don’t radiate back. The effect of irradiation is exhibited through the change in colour due to the distortion in the crystal structure. The change in colour is permanent and so is the non-radioactive state of the gemstones.

Hence, irradiated gemstones are absolutely hazard-free.

A look at Prominent Diamond Cuts since 13th Century

Going back to the 12th century, we will find the first instances of how diamond cutting became a trade of respectable position in the society. As royal families and noblemen began to showcase their pomp and glory through silk and gemstones, diamond slowly began to raise its head as one of the most precious items of collection in the treasury. The first diamonds were cut in manner that resembles the modern Point Cut. We are not talking about the trend in the year 1970, but in 1287.

Diamond Beads

Here are some truly antiquated diamond cuts that still retain their place in modern day gem cutting trends.

Natural Points:

Diamonds that crystallised in octahedral and do-decahedral crystal lattices are left uncut. These are natural crystals and have remained so for millennia. Before America and Australia were discovered and conquered, the only source of diamonds was the Indian sub-continent. A Point Cut diamond is actually a misnomer as there are no tools involved in the machining.

Pyramidal Point Cut:

Grinding became a regular gem cutting and polishing technique, especially after 15th century. Big diamonds were smoothened and polished without taking away their size. Out of multiple girdle profiles, a lapidary artist would choose the one with the largest contour in diamonds. Diamonds have always carried the charm of bestowing magical and healing effects on the person wearing them. Keeping them untouched and natural was no longer a fashionable trend. Hence, slight polishing using Pyramidal Point Cuts made at shallow planes compared to natural points became more popular.

The Burgundian Point Cut:

Burgundian Point Cut is preferred for diamonds with dodecahedral crystals structure. This crystal lattice has many irregularities and requires intensive polishing. The dodecahedron crystal is aligned in a way that the four faces seem as if rising upwards.

Table Cuts:

A remarkable refreshing cutting pattern, diamonds were first cut in Table Cut using diamond dust itself! The first Table Cut diamond was shaped like alphabet “M”. It was probably the first engagement ring ever gifted. Not to forget, before Rose Cut diamond became the symbol of love and romance, Table Cuts were the fashionable items.

Diamond Beads

Old Mine Cushion Cuts:

Europeans dug out new sources of diamond gemstone. Amazon and Sahara became the diamond potboilers for traders. The new cutting models for vibrant diamonds beads meant embracing an indigenous gem shaping technique. Old Mine Cushion Cut took birth in the 18th century bearing an uncanny resemblance to what we know as Modern Brilliant Cut. They gave birth to the aristocratic cuts like marquise cut/navette cut.

Old Mine Cushion Cut was produced using bruting machine powered by steam, and later motors. English Round Cuts were borne from the improvements in diamond bruting machines, some of which produced 58 flawless facets in a single diamond gemstone!

Asscher Cut:

Named after the world renowned gem cutters, the Asscher Brothers of Holland (they cut the world’s largest diamond- Cullinan), this is very similar to what we call Square Emeralds bearing large facets, small table and an elongated crown.

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.