How many purity groups does sapphire have?

Precious stones (stones of the first category) include : diamond, sapphire, emerald, ruby, natural sea pearls. The cost of a gemstone depends on its characteristics. It cut, weight, color and clarity.
Color and purity are given to the stone by nature, but only the masterly work of a master cutter endows the stone with magnificent play and reveals its beauty. The weight Gemstones are measured in carats (ct). One carat is equal to 0,2 grams.
Color – the degree of visual sensation of color, its tonality and saturation.
Most natural materials are characterized by inclusions and defects, but their artificial analogues do not have defects, which actually indicates their laboratory origin. Diamond – the most expensive and beautiful gemstone. By weight Diamonds are divided into three categories: small (up to 0,29 carats), medium (from 0,30 to 0,99 carats) and large (from 1,00 carats and more).
If the price of one individual gram of gold and one gram of a kilogram are the same, then the cost of diamonds increases progressively as their size increases. Color A diamond is rarely completely transparent, but it is the one that is most valuable. The price can reach tens of thousands of dollars per carat. But stones that have impurities that determine the color are much cheaper. The closer the color of a diamond is to a yellow-brown hue, the more negatively this affects its price.
Russian classification by color assumes 9 color positions for diamonds:
1, 2 – colorless diamonds
3, 4 – slightly yellowish diamonds
5, 6 – pronounced yellow tint diamonds
6, 7 – yellow diamonds
8 – yellow-brown diamonds
9 – brown diamonds
The exception is the so-called fancy diamonds – pink, green, red, blue, etc. Such stones (especially pink ones) are very rare and sometimes cost more than transparent ones. Purity or transparency diamonds can have a very significant impact on the price of the stone – two stones of the same weight can have prices that differ several times. It’s all about the presence of internal inclusions and defects – the more of them, the lower the cost of the stone.
The Russian classification provides 12 items for assessing cleanliness diamonds:
1 – no defects
2 – subtle defects
3, 4 – minor defects
5, 6 – small defects or minor inclusions
7 – small inclusions
8, 9 – inclusions visible to the naked eye
10, 11, 12 – numerous inclusions are clearly visible to the naked eye Traditional cut shape for a diamond – round with 57 facets (Kr-57). This is the most common and expensive cut. The stone is capable of reflecting almost all the light falling on it and has a truly dazzling effect.
In addition to the round diamond, diamond shapes called fancy (marquise, princess, oval, pear, emerald, heart, baguette) are also popular, each of which is beautiful in its own way and looks great in jewelry. Taking into account these characteristics, you can easily “decipher” the meaning of the abbreviation of the label, which at first glance seems wise:
2 BrKr57 0,11 ct. 3/2
where 2 Br is the number of diamonds; Kr 57 – round cut with 57 facets; 0,11 ct – total weight of diamonds in carats; 3/2 – characteristics of flowers/purity. Ruby – This bright red gemstone can often be seen in rings or earrings. Rubies, like diamonds, have different values, which depend on their weight, quality and color.
The color scale of rubies starts with light pink Thai stones (color characteristic – 3), which are not very highly valued, and ends with fiery red saturated rubies from Burma (color characteristic -1). The cost of such rubies is close to the price of diamonds, especially if the purity indicators are also quite high. Sapphires – These are minerals of a magnificent cornflower blue color. The deeper the blue hue, the more expensive the stone.
1 – bright blue, with a cornflower blue tint.
2 – moderately saturated blue
3 – light blue
There are also yellow, green, orange and even colorless sapphires, which are often tried to be passed off as diamonds. But sapphires themselves are also often counterfeited – it can be ordinary colored glass, tourmaline or cyanite. A fake can be distinguished by the absence of natural impurities and inclusions in the structure of the stone. Emeralds They are attracted by their green tint, which can be more or less saturated and bright.
Depending on the color tone and lightness, emeralds are divided into five color groups:
1 – dark green
2 – medium-dark green
3 – medium green
4 – medium-light green
5 – light green
Naturally, Colombian emeralds with a rich grassy hue are valued tens of times more expensive than light green stones from Africa or Brazil. It is quite difficult to recognize a natural stone – modern technologies make it possible to artificially grow emerald with inclusions. By cleanliness faceted rubies, sapphires and emeralds are divided into 3 groups depending on the number and location of defects in the stone:
G1 – transparent, have barely visible inclusions or cracks
G2 – transparent, inclusions and cracks form condensations and a network in individual zones of the stone, visible to the naked eye.
G3 – with areas of cloudiness that have partially lost their shine and play.
There are stones that are not assigned a purity category. Stones of the so-called “ornamental” quality. They are often used in silver products.
Cabochon-cut stones are divided into 2 groups:
K1 – partially transparent, there are inclusions and cracks visible to the naked eye.
K2 – opaque, have a dense network of visible inclusions or cracks. A separate a word about pearls.
Pearls are considered a precious stone, of course, only if we are talking about real pearls of organic origin. Such natural pearls are highly valued, but cultured pearls are several times cheaper. Middle-class jewelry mainly uses cultured sea pearls, as they are more affordable. But don’t confuse cultured pearls with imitation pearls! Imitation is plastic coated with mother-of-pearl enamel. Pearl evaluation criteria: Size, Shape, Thickness of mother-of-pearl layer, Surface evenness, Color, Shape. ————
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(499) 497-43-01 Sapphire is a unique gemstone that has long been endowed with various magical properties. The first mentions of the blue mineral appeared in Southeast Asia many centuries ago. Residents of this territory often found opaque grayish stones that were exceptionally hard. It was then that the name “corundum” appeared, but subsequently this term began to be used to refer to a wide group of minerals. Today, sapphire is considered one of the varieties of corundum, and perhaps the most famous.

History of the stone and magical properties

The ancient Greeks and Jews confused blue corundum with other minerals, so sapphire was often called lapis lazuli and lapis lazuli. But in Rus’, sapphires were called “yakhonts”: they were used to decorate royal crowns, clothing and church utensils. For a long time, the mineral was considered magical and magical. It was believed that sapphire would help a person maintain strength, optimism and vigor. The stone was also worn to resolve conflicts with others and avoid health problems. It was believed that a person wearing a sapphire amulet constantly receives great energy replenishment. The stone makes him more insightful and gives him psychic abilities. Of course, there is no direct confirmation of these properties, but many still pay increased attention to such extraordinary qualities of the gem. For example, sapphire is often given to creative individuals, as it is believed that it will help in finding interesting ideas. For those who do monotonous work, blue corundum is also no less useful: it helps to become more patient and collected. For kids, buy a yellow mineral that helps develop courage and endurance. But black sapphire is considered protection against slander and envy. A lot of interesting things about the stone can be found even in the dream book. For example, it is believed that a sapphire in a woman’s dream indicates a rival in her personal life. And a dream of a ring with blue corundum promises love quarrels. If the mineral lies on the road, then this indicates a loss of strength – in this case, it is worth taking a break from everyday activities in order to recover physically and spiritually.

physical characteristics

• Chemical formula – Al₂O₃.
• Gloss – pronounced, glassy.
• Transparency – varies depending on the variety (stones range from transparent white to opaque black).
• Hardness on the Mohs scale – 9 (out of 10 points).
• Density – approximately 3,9–4,0 g/cm3.

The mineral has a conchoidal fracture and is considered very durable and non-fragile (with the exception of some species). It has an extremely high melting point – approximately 2040 °C.

Sapphire shades

Mineralogists call dark blue corundum sapphires, but other specimens of the mineral that have a fancy color are also found in nature. All varieties have the same chemical formula; the differences lie only in the composition of the impurities.

Let’s look at each type in more detail:

• Blue. These minerals have a rich cornflower blue hue and are used as a color standard for other varieties of corundum. Mined in India and Kashmir.
• Yellow. A common type that can often be found in jewelry. The color palette varies from translucent pastel yellow to bright orange. This difference is explained by different iron content. Yellow sapphire deposits are located in Sri Lanka, Tanzania and Burma.
• Pink. They are often called “padparadscha”, which means “lotus color”. The shade of sapphires is truly amazing – soft pink, with a slight pearlescent tint. It is a very rare species, which is why it is more expensive than others. Minerals are mined in Thailand.
• Blue. Another rare species that is found in Australia and Sri Lanka. Most often they have a translucent structure and a delicate bluish tone.
• Purple. They are often called “oriental amethysts”, since their color is very similar to this stone. The purple color is due to the high vanadium content. Gems are mined in Australia.
• Black. They contain impurities of iron and titanium, which is why they acquire such a dark shade. The more impurities, the more saturated the color of the mineral. Stone deposits are known in Tanzania, Thailand, Sri Lanka and Australia.
• Colorless (white). In nature, such sapphires are very rare. Their structure is much more fragile and capricious to process than their “brothers”. The deposits are located in the USA, Brazil and Africa.
• Star-shaped. The most valuable sapphires have a unique property: when light hits them, they form a star on the surface. This phenomenon is called asterism. The stones are very rare, so they are valued in jewelry.

Synthetic sapphires

Thanks to modern technologies, today it has been possible to establish the production of artificial or synthetic sapphires. The first artificial mineral was synthesized back in the 20th century. In 1904, the French chemist Auguste Verneuil discovered a synthesis method using droplet deposition in an oxygen-hydrogen flame. Around the middle of the century, the first large-scale production of such minerals was established in the United States. Today, synthetic gems are manufactured all over the world, including in Russia – the largest Monocrystal plant is located in Stavropol.

The most widespread are two varieties:

• Leucosapphires. Optically transparent stones that have the highest hardness and heat resistance. Due to this, artificial sapphires have found use in the manufacture of wear-resistant and heat-resistant products.
• Sapphires activated with Ti3 ions. Such minerals are large in size and can be used in mechanical engineering and the production of specialized equipment.

The main difference between artificial stones and natural ones is the absence of inclusions, but this can only be seen under a microscope. Also, synthetic sapphires have a greenish tint that appears under an ultraviolet lamp (natural stones have a white tint).

Application

Almost all varieties of sapphires are used in jewelry in the form of cuts. Of course, most often there are inserts made of blue minerals, less often – products with yellow or purple minerals. The rarest type – star sapphire – is cut as a cabochon (that is, it is given a smooth elongated shape without edges), since it is this cut that allows the effect of asterism to be revealed.

Synthetic sapphires can be called more functional, since in addition to being used in jewelry, they are often used in industry. For example, leucosapphires are used to produce ophthalmic scalpels and eye lenses. Stones have also found application in the manufacture of optically transparent elements. It can be:

• space station windows;
• protective glasses for phones;
• optical elements for missiles and aircraft;
• glass in watches and cameras.

Another area of ​​use is dentistry (for example, for the manufacture of aesthetic braces). Such widespread use is due to the excellent physical properties of artificial leucosapphires: they do not interact with alkali metal vapors, have a high melting point and withstand pressure changes.

Another type of synthetic stone, Ti3 ion-activated sapphires, is often found in titanium-sapphire lasers.

How to wear sapphire jewelry

The most popular products made from blue corundum are rings. They are usually worn on the index finger of the right hand. Wedding rings with such a stone are often chosen – it is believed that it makes a marriage more prosperous, and it is easier to wear and care for than the beloved diamonds.

Earrings and pendants with such a precious mineral are also in great demand. Ideally, if they are made in the form of a set – then the color and brightness of the inserts match each other as much as possible.

If you like extravagant looks, then you can combine jewelry with sapphires of different shades. Blue, purple and yellow stones go well together. If necessary, they are supplemented with other varieties of corundum.

How to decipher a sapphire product tag

Now let’s talk about another important nuance – deciphering the jewelry tag. This way you can understand what kind of stone you are purchasing.

For example, consider the inscription: “1 Sapph. M G 6*4 3/2 0,6ct.”:

• The first number is the number of stones in the product.
• “Sapph.” (or simply “C”) is the name of the gemstone used.
• “M” is a marquise cut, “G” is a pear-shaped stone. Instead of this letter there may be another designation (for example, “Ov” – oval, “P” – princess, etc.).
• Further in the designation there may be an additional number, for example, 53. This means the number of facets in the cut (if it is preceded by “Kr.”). However, in our case we used a shape without edges.
• 6*4 are numbers indicating the size of the stone.
• 3/2 are indicators of the color and purity of the mineral. The number “3” indicates that the stone in the jewelry has a rich blue tint (“1” and “2” are used for sapphires of lesser saturation), and the “2” after the fraction indicates inclusions that are visible under magnification (for visible inclusions use “3 “, for stones of high purity – “1”.
• 0,6ct. (or simply 0,6) – the weight of the sapphire in carats.

As you can see, everything is quite simple, so you can easily figure out these numbers on your own. And if you have any difficulties, the specialists of our Petrogold online store will definitely help you!

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