what is synthetic spinel

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Are synthetic spinels valuable?

Furthermore, synthetic spinel is inexpensive and common. It has frequently been used as a simulant for other gems in class rings and birthstone jewelry, which has affected its public perception. Natural spinel, however, has always been a rare and beautiful gem.

Is spinel real or synthetic?

Fluorescence under UV rays: A Natural Spinel has the strongest fluorescence under a long wavelength and weak to absent under a short wavelength. While, Synthetic Spinels have strong fluorescence under a short wavelength and may often a bright blue, chalky green, or red fluorescence.

Are spinels fake diamonds?

The proper way to analyze whether Spinel is real is to put it under a UV Radiation Light. Set it to long-wave and look for any stones that are particularly glowy. If the stones are glowy, that means it's synthetic and not natural.

How can you tell a fake spinel?

0:231:18How to detect synthetic spinel from natural spinels. - YouTubeYouTubeStart of suggested clipEnd of suggested clipAs. You clearly see we have a lot of stones but when we put on the UV radiation light on the shortMoreAs. You clearly see we have a lot of stones but when we put on the UV radiation light on the short sorry long wave clearly. See you can clearly see that the one piece that is shining is synthetic.

What is synthetic spinel made of?

synthetic spinel is produced by using flux-grown or flame-fusion method as synthetic corundum in a variety of fine colors. In chemical and physical properties nearly identical with true spinel. Widely used as gemstones and as imitation such as imitation of lapis lazuli and moonstone.

Can you wear spinel everyday?

An 8/10 on the Mohs Hardness scale, it's a durable gem for daily wear.

Is spinel a good gemstone?

Like ruby, spinel is found in alluvial deposits; it ranks 8 on the Mohs scale and has good toughness, making it a durable gem for jewelry. Well-formed spinel crystals are in high demand among mineral collectors.

Is spinel an expensive gem?

Top Spinels in the 2 to 5 carat size will often sell for $3,000 to $5,000 a carat. For the very rare stones over 5 carats, prices in the range of $8,000 to $10,000 per carat are not unusual for the top colors.

Which is better spinel or sapphire?

Spinel has a hardness of 7.5-8, which appears close behind its September counterpart. However, the Mohs Hardness Scale is not linear, and sapphire is actually twice as hard as spinel. With good toughness and stability, spinel is still a fairly durable stone.

How can you tell if a stone is synthetic?

Synthetic gemstones are more likely to be rich and vivid in color, and are virtually inclusion or blemish-free when you look at them. Almost always, natural gemstones will have some type of inclusion or color differentiation.

Why is spinel so expensive?

However, it is expensive compared to many other semi-precious gems and other jewelry birthstones. This is due to how rare spinel is, especially blue or faceted spinel. Spinel is 100 times rarer than both sapphires and rubies.

Does spinel scratch easily?

The black spinel is given a rating of 8 on the Mohs scale of hardness, meaning it is both tough and durable. This also makes it hard to scratch and chip, making it a smart choice for jewelry that you might wear daily.

Is spinel a real gemstone?

What is a spinel gem? Spinel is a mineral that owes its beautiful color to chromium, much like rubies and emeralds do. It has a hardness of 8 on the Mohs hardness scale (diamond has a hardness of 10). Spinel is seen in a wide range of colors: red, lavender, violet, blue, green, brown, black.

Is spinel man made?

Man-made spinel is used extensively. Discovered accidentally when scientists were experimenting to try and produce a flame-fusion blue synthetic sapphire, spinel's great advantage is that it can be made to reproduce almost all colors except purple.

Why is spinel so expensive?

However, it is expensive compared to many other semi-precious gems and other jewelry birthstones. This is due to how rare spinel is, especially blue or faceted spinel. Spinel is 100 times rarer than both sapphires and rubies.

When was synthetic spinel first made?

BACKGROUND Synthetic spinel was first produced in the mid-1800s-not by flame fusion as is usually thought, but by flux growth (Nassau, 1980). These first, small flux synthetic spinel crys- tals were accidentally grown during a n attempted synthesis of corundum.

What is synthetic spinel?

Synthetic spinel, was first produced accidentally during an attempt to make a satisfactory blue synthetic sapphire by the Verneuil process. The addition of cobalt oxide, which seemed a logical source for the blue sapphire, was found to give a very uneven coloration. As a result, an attempt was made to substitute for the cobalt oxides tinctorial agents, but without marked success. Then it was decided that magnesium oxide might act as a flux when added to the aluminum oxide and distribute evenly the color imparted by the cobalt oxide. The color was very even, but a study of the characteristics of the resulting boules showed that they were squarish in outline (Figure 5). Further investigation proved the material to be not sapphire but a magnesium aluminate with the structure of spinel, rather than that of corundum.

How to identify synthetic spinel?

There is another method by which synthetic spinel may be identified readily in certain instances. The cobalt coloring in blue stones can be detected by the use of the spectroscope, for the cobalt lines are usually prominently visible at 6350 A.U. in the orange, at 5800 A.U. in the yellow, and at 5400 A.U. in the green.

What color is the spinel?

In dark-blue and lapis-colored material, the bands in the orange and yellow are particularly broad about twice the width of the line in the green. In light-blue material, the three bands are much less strong. Occasionally, a bright-red fluorescent line is visible in the deep red. Natural blue spinel shows a band in the orange at 6320 A.U., with a stronger and sharper band at 4800 A.U. and a strong broad band at 4590 A.U.; this is caused by ferrous iron. Synthetic yellow spinel shows two lines in the blue-violet at 4450 A.U. and a very sharp line at 4220 A.U. in the violet. Greenish-blue material exhibits a spectrum that combines the one in the blue caused by cobalt and the one in the yellow caused by manganese. Alexandrite like stones have a broad absorption in the yellow-green.

What is the closest R.I. to synthetic spinel?

The stone it may resemble most closely in appearance is the one with the closest R.I. of the important gems; alexandrite. The usual so-called synthetic alexandrite is a synthetic sapphire that bears little resemblance to the genuine chrysoberyl variety, in that it changes from a color similar to that amethyst to a gray-blue. The rare synthetic spinel changes from brownish red to green; therefore, they are easily mistaken in appearance. Although the 1.74 to 1.75 R.I. of alexandrite is close to the 1.73 of synthetic spinel, the strong trichroism of the natural identifies it readily.

Why is spinel made?

First, because it is slightly softer than synthetic corundum, it can be fashioned more rapidly and less expensively. Secondly, several of the colors in which it is made are better imitation for a number of natural stones than those made in synthetic corundum.

Is 1.715 a synthetic spinel?

and a strain-free reaction in the polariscope is sufficient to identify natural spinel. The natural is comparatively rare without inclusions of any kind, although perhaps less rare in an internally flawless state than most of the other natural stones. In other words, flawlessness is perhaps more common for synthetic spinel than for most other gemstones.

Does spinel have bubbles?

As a result, it is not unusual for bubbles to be entirely absent in spinel. When they do occur, however, usually they are minute and distributed randomly throughout the stone, although not as highly concentrated as in Figure 7. Irregular, somewhat elongated bubbles also may be encountered (see Figure 8), as well as ones that appear angular because of numerous, flat faces (Figure 9).

What are synthetic spinels ?

Synthetic Spinels are the artificial counterparts of stones like aquamarine. They are quite easily created in the labs with a fusion of the constituents and minerals present in the natural gemstones like aquamarine. Infused with flame and churned out to be a rock of a similar appearance synthetic spinels are quite cheap compared to natural stones. They are extensively used in the jewellery sectors are yield quite high demand with its looks and constituents.

What are the benefits of synthetic spinel ?

Synthetic aquamarine can help you become more faithful loyal and courageous if you sport one. It can make people more responsible, alert, and aware. They are useful as meditative stones. Often believed to be lucky stones by sailors due to its connection with the colour of the sea, it is commonly used by quite a few to protect them on voyages.

How were synthetic spinels created?

It is known that synthetic spinels were created while producing a blue sapphire. The accidental introduction of synthetic spinel proved as a landmark in this industry. In place of the coveted blue sapphire, synthetic spinel, like the synthetic aquamarine was created. It is a replica of the real and natural aquamarine. Synthetic aquamarine is quite cheap and affordable as compared to genuine aquamarine, which is highly expensive.

When was synthetic spinel invented?

Synthetic spinel. Synthetic spinel, accidentally produced in the middle of the 18th century, has been described more recently in scientific publications in 2000 and 2004. By 2015, transparent spinel was being made in sheets and other shapes through sintering.

What are the properties of spinel?

Properties. Spinel crystallizes in the isometric system; common crystal forms are octahedra, usually twinned. It has no true cleavage, but shows an octahedral parting and a conchoidal fracture. Its hardness is 8, its specific gravity is 3.5–4.1, and it is transparent to opaque with a vitreous to dull luster.

What is the largest spinel in the world?

The Samarian Spinel is the largest known spinel in the world, weighing 500 carats (100 g). The transparent red spinels were called spinel-rubies or balas rubies. In the past, before the arrival of modern science, spinels and rubies were equally known as rubies.

What is the name of the magnesium/aluminium member of the larger spinel group?

Spinel ( / spɪˈnɛl /) is the magnesium/aluminium member of the larger spinel group of minerals. It has the formula MgAl. 2O. 4 in the cubic crystal system. Its name comes from the Latin word spinella, which means spine in reference to its pointed crystals.

What color are spinels?

Since 2000, in several locations around the world, spinels have been discovered with unusual vivid pink or blue colors. Such "glowing" spinels are known from Mogok (Myanmar), Mahenge plateau (Tanzania), Lục Yên District (Vietnam) and some more localities. In 2018 bright blue spinels have been reported also in the southern part of Baffin Island (Canada). The pure blue coloration of spinel is caused by small additions of cobalt.

Where is Spinel found?

Spinel has long been found in the gemstone -bearing gravel of Sri Lanka and in limestones of the Badakshan Province in modern-day Afghanistan and Tajikistan; and of Mogok in Myanmar.

Is spinel a mineral?

Spinel is found as a metamorphic mineral in metamorphosed limestones and silica-poor mudstones. It also occurs as a primary mineral in rare mafic igneous rocks; in these igneous rocks, the magmas are relatively deficient in alkalis relative to aluminium, and aluminium oxide may form as the mineral corundum or may combine with magnesia to form spinel. This is why spinel and ruby are often found together. The spinel petrogenesis in mafic magmatic rocks is strongly debated, but certainly results from mafic magma interaction with more evolved magma or rock (e.g. gabbro, troctolite).

When was the first synthetic spinel made?

13. Synthetic Spinel. Synthetic spinel was first produced in 1847, but little was used in jewelry until the early 1900s. By the 1930s, synthetic spinels in a wide variety of colors were being made by the Verneuil and flux growth processes.

What are spinel crystals?

Crystals of Spinel: Much spinel is found as beautiful crystals in white marble. The crystals are often shaped like perfect octahedrons and frequently have colors that mimic ruby and sapphire. In the early days of gems, these red and blue spinels were often misidentified as ruby and sapphire.

What color are blue spinels?

Many blue spinels receive their color from trace amounts of iron, but the most vibrant blues are colored by traces of cobalt. Purple and orange spinels are colored by traces of iron and chromium. Pink Spinel: A faceted pink spinel with a brilliant luster. Photo by Greg C. Grace / Alamy Stock Photo.

When was spinel named a birthstone?

One of the most important things that can influence the popularity of a gem is to be named as a birthstone. That happened for spinel in July 2016, when the American Gem Trade Association and the Jewelers of America named it a birthstone for the month of August.

Is spinel rarer than ruby?

Spinel is many times rarer than ruby, has comparable color, luster, and a wonderful appearance - but it sells for a fraction of the price. Why is that? An important reason is that jewelry manufacturers and jewelry buyers are still not thinking about spinel - and that makes spinel a gem that does not have a high demand - yet!

Where does spinel come from?

So, where to find this incredible gem? Spinel can be found on several continents, from Brazil in South America, Kenya in Africa, and especially across the southern portion of Asia, stretching from Afghanistan to Vietnam. It has been commonly found in gravel beds in Sri Lanka, Tanzania, and Madagascar, and marble deposits in Vietnam.

What is the chemical formula for spinel?

The chemical formula for spinel is MgAl₂O₄.

What is the value of a spinel gem?

Now that we know the science basics of spinel, what makes it such an interesting gemstone?

What is the most famous spinel?

One of the most famous spinels in the world is the Black Prince’s Ruby, the 170-carat gem that adorns the U.K.’s Imperial Crown. And the Timur Ruby, also part of the British crown jewels, is actually a 361-carat polished red spinel. The Black Prince’s Ruby is the largest uncut spinel in the world, and once decorated King Henry V’s helmet during battle.

What color are spinels?

Found in a variety of colors, including red, blue, violet, and dark green, spinel gemstones are regaining their popularity of old.

Is Spinel a one of a kind gem?

Spinel is clearly a one-of-a-kind gemstone, with a lot of history and cool features that make it unique. The next time you’re searching for a gem, why not choose this inviting selection? Visit an AGS jeweler near you!

Is spinel more expensive than ruby?

You may be surprised to know that spinel is rarer than ruby, but this has not affected its price (yet). Although spinel is still less expensive than ruby, the market for spinel has been increasing.

What element is used to make red spinel?

Red spinel is colored by chromium, the same trace element that colors ruby and emerald.

What is the best color for spinel?

Stunning Color. The finest red spinel colors are pure red to slightly purplish red hues of medium to medium-dark tone. Cut for Brilliance. Spinel is most often cut in cushion and oval shapes; when properly proportioned it has excellent brilliance. Chromium.

Why is spinel red?

Like ruby, the color of red spinel is due to traces of chromium. Spinel belongs to the cubic crystal system and its characteristic crystal shape is an octahedron, which looks like two back-to-back pyramids.

Is spinel a ruby?

Until recently, spinel was an underappreciated gem with little consumer recognition. Increasing demand for ruby alternatives rekindled appreciation for spinel’s rich red color and history. In ancient times, southeast Asia’s mines yielded exceptional large spinel crystals, which became the treasured property of kings and emperors, often passing through many hands as spoils of war.

How are synthetic spinels made?

The Flame-Fusion Method: This method of producing Synthetic Spinels occurs accidentally while producing synthetic Corundum in 1908. A Natural Spinel has a ratio of MgO to Al2O3 is 1:1. Verneuil Synthetics are produced by changing the ratio to 2:1 (doubling the amount of alumina). The increased amount of alumina resulted in an increased Refractive Index (1.727) and Specific Gravity (3.64).

Where are spinels found?

The most significant deposits of Spinels occurred in Myanmar (Burma), Sri-Lanka (Ceylon), Cambodia, Thailand, Brazil, Madagascar, Nepal, Tanzania, Tadzhikistan, Afghanistan, and Australia. Spinels come in a variety of colors which range from blue spinel, red spinel, green spinel, yellow spinel, brown spinel, ...

Why are natural spinels orange?

Some light-colored and orange color of Natural Spinels is colored due to chromium, which causes it to be repelled by a magnet. 3. Refractive Index and Specific Gravity: The Natural Spinel has a Refractive Index of 1.72, in the case of Red Spinel it is 1.74 and in Zinc-rich Spinel it can be1.805 (rare to be found).

What is the specific gravity of a spinel?

Synthetic Spinels has a noticeably different R.I. of 1.727-+0.001. The specific gravity of Natural Spinels has S.G. ranges 3.58-3.61, Zinc rich Spinels have S.G. as high as 4.40. Synthetic Spinels has S.G. ranges between 3.63- 3.64.

What color are spinels?

Spinels come in a variety of colors which range from blue spinel, red spinel, green spinel, yellow spinel, brown spinel, black spinel, orange spinel, pink spinel to violet spinel. But the rarest Spinel is Cobalt Blue Spinel which has a rich deep blue color.

How much does a spinel cost?

5. Price: There is a big difference between the price of Natural and Synthetic Spinels. A Natural Red Spinels range starts from 100$/carat and goes till 5, ooo$/carat. Price varies from color to color; red is the costliest, followed by blue, then pink, and in the last multi-colors. Synthetic Spinels are very cheap. They are easily available in the market at a price of 1$/carat-2$per carat.

Which type of spinel has the strongest fluorescence?

4. Fluorescence under UV rays: A Natural Spinel has the strongest fluorescence under a long wavelength and weak to absent under a short wavelength. While, Synthetic Spinels have strong fluorescence under a short wavelength and may often a bright blue, chalky green, or red fluorescence.

What is spinel used for?

Used with permission. Although spinel has been used in jewelry since ancient times, this gemstone has only recently received the attention it deserves. Before the rise of modern gemology in the late 19 th and early 20 th centuries, spinel was often identified as corundum, as they are often found in the same mines.

What color are spinels?

Spinels range from strong, deep colors to very light pastels, coming in all shades of pink, lavender, red, red-orange, purple, blue, and even black. (Only pure green and yellow appear to be absent). These gems are found on every continent. The varieties are usually referred to by their color. The red and blue varieties are perhaps the most celebrated since they were historically identified as rubies and sapphires. (Spinels are also close to corundum in terms of luster and hardness).

Where are spinel gems found?

Found traditionally and mainly in Afghanistan, Myanmar, and Sri Lanka, spinels have been discovered more recently in various sites in Africa, Australia, Russia, and Vietnam. These gems are usually not mined from the hard rock primary deposits in which they form but instead from alluvial or placer deposits where eroded material has been washed downstream. These “gem gravels” may contain other species in addition to spinel. The rough and tumble action has smoothed these crystals into rounded shapes and removed much of the included and fractured parts of the gem rough. This alluvial rough is easily recovered material that’s great for faceting.

How many carats are in a spinel?

Spinels are known up to hundreds of carats in various colors.

What are the most common chromophores in spinel?

Chromium, iron, and cobalt are the most common chromophores in spinel. The majority of jewelry gems, such as beryl (emerald, aquamarine, etc), corundum ( ruby and sapphire ), quartz, and topaz, are allochromatic. All have colorless varieties formed without the color-making impurities.

Where are alluvial spinels mined?

Alluvial spinels and rubies, mined in Vietnam. Image courtesy of Gems from Earth.

Where are star spinels cut?

Star stone spinels with 4-rayed stars have occasionally been cut from gray or grayish blue to black stones from Myanmar. A 6-rayed star can be seen in such material if oriented along the 3-fold symmetry axis of the crystal (parallel to the edges of an octahedral face).

Overview

Synthetic spinel

Synthetic spinel can be produced by similar means to synthetic corundum, including the Verneuil method and the flux method pioneered by Edmond Frémy. It is widely used as an inexpensive cut gem in birthstone jewelry for the month of August. Light blue synthetic spinel is a good imitation of aquamarine beryl, and green synthetic spinel is used as an emerald or tourmaline simulant. By 2015, transparent spinel was being made in sheets and other shapes through sintering. Syntheti…

Properties

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