Tips for stone care

How to distinguish natural aquamarine from a fake?

Aquamarine is a gem known since ancient times. In order to consciously choose the specimen that is right for you, you need to understand the issue of determining and the value of its characteristics: which color is better, which cut is preferable, where are gem-quality crystals mined? In this article we talk about the nuances that do and do not affect quality, and, accordingly, cost:

Color

Gem-quality aquamarine is a transparent stone, a type of the mineral beryl. The name of this gem translates as “sea water”, that is, aquamarine has the color of the sea, which, by the way, can be very different. The color palette includes blue and blue tones. Green is often used as an additional shade. In nature, aquamarines in most cases have a very light color, often with a clearly visible greenish tint. Sometimes it is so light that it can appear almost colorless, white, but a bluish tint should still be present. Blue stones are much less common in nature. Stones with a rich blue color are called “machiche” or “maxis”, after the name of a mine in Brazil; the color of such stones is not stable and often fades in the light. Aquamarines with a bright and rich blue color (deep blue) have the commercial name Santa Maria. Please note that the saturation of aquamarine depends on its weight. That is, specimens up to 1-2 carats will look almost colorless, even if the raw material from which they were cut looked blue. As the mass increases, the stone looks more saturated. The color of aquamarine directly affects the cost. The brighter and more saturated the color, the higher the cost. For example, an aquamarine of a medium blue tone (Medium blue) will be approximately 2-3 times cheaper than a sample of a saturated blue shade (Deep blue), all other characteristics being equal, and 2-3 times more expensive than a very light greenish blue sample. Keep in mind that greenish shades reduce the price.

Ennobling

It should be noted that aquamarine is often refined. This may include heat treatment of yellow heliodor beryls to impart a more valuable blue color, and irradiation of less saturated samples. At the same time, refining is not diagnosed by most laboratories and the fact of refining does not affect the price of the carat. It can be assumed that most blue aquamarines received their color through one of the refining methods. However, there are also non-ennobled ones. It is generally accepted that a light bluish-greenish color indicates a natural color, but this is not always the case. When purchasing, it is important to trust the seller, who tracks the history of his stones and has information about where a particular crystal was mined and whether it was refined. However, in most cases this data remains unknown.

Cleanliness

In the photo: A specimen of aquamarine with high purity Aquamarine crystals with clear zones suitable for cutting can reach very large sizes. Therefore, high purity in cut aquamarine is accepted by default. Probably, among all the precious and semi-precious stones, the phrase “stone of pure water” is most applicable to aquamarine. According to the GIA purity grading system, aquamarines are classified as Type I – usually clear. For our catalog we select mainly visually clean (eye clean, VVS according to the GIA marking), clean under a magnifying glass (loupe clean). If there are obvious defects in the form of noticeable inclusions and cracks, the price is reduced significantly, by more than 50%, compared to stones of similar characteristics. Samples with inclusions are often used to make cabochons. Two-phase gas-liquid inclusions, as well as mica, may occur. Rarely, crystals contain etching channels. They are thin, silky villi-like hollow tubules, equally oriented. If such a sample is correctly oriented during processing and cut into a cabochon shape, then the cat’s eye effect can be revealed in the stone. This effect in aquamarines is not as bright and pronounced as, for example, in chrysoberyl or tourmaline. But, nevertheless, it can have collection value and be decorative, especially if the blue color is well expressed.

Weight

Aquamarines are extremely rarely cut for “sprinkling”, since in small sizes stones up to 1 carat do not look blue, rather colorless. The color begins to be clearly readable when the stone weighs more than 2-3 carats. In the 5-10 carat size, aquamarines are very attractive, the blue color of beryl is well expressed, and this is probably the most suitable size for an elegant ring or pendant that is comfortable to wear every day. They look sophisticated, discreet, but at the same time expensive and noble. Products with such stones are made individually and to order. Pieces weighing 15-20 carats are used to create unique jewelry for going out: intricate cocktail rings, diamond necklaces and luxurious pendants that fit perfectly into a red carpet look. As mentioned above, aquamarine crystals in nature can be impressive in size and weight. For this reason, sometimes there are offers of collectible items on the market. These are really large, large examples of aquamarine, the size and weight of which limits their use in jewelry, and, as a rule, they decorate interiors and private collections.

Cutting

In the photo: Aquamarine with a “large face” Calibrated small light aquamarines are sold in a range of standardized sizes and shapes: circle, oval, rectangle. Larger samples are cut individually. Due to the elongated shape of the crystals, the most advantageous and popular cut of aquamarine is the stepped (emerald) cut. With this form, the yield of pure crystals when cutting is greatest, compared to other forms. Octagons, aschers and baguettes with correct, harmonious proportions in a step cut are very beautiful. Sometimes, instead of tiers-steps, wedge-shaped, princess (square) and radiant (rectangular) cuts are used, which look simply amazing! But there is also a downside: often cutters, in pursuit of profit, use almost the entire length of the aquamarine crystal, so that the cut baguettes (rectangles) become like long thin sticks. It should be rightly noted that some jewelry houses like to play with this shape with an individual design, and quite successfully, but in most cases, “sticks” due to their non-standard shape are of little demand, firstly, and secondly, there is a risk of damaging such a stone when setting and great cut In addition to octagons and baguettes, cushion, pear, and oval shapes are popular. Pear-shaped aquamarines are used to create a romantic image of raindrops, for example, in earrings or a pendant. A pear-shaped aquamarine set in a ring will visually lengthen your fingers. For aquamarine, as for other jewelry stones, the quality of processing is important. Three main cutting criteria can be distinguished: proportions, summary and polishing of the edges. Good cut quality means that all three parameters are presented at a high level. Aquamarines are highly polished, so there should be no noticeable tool marks on the surface of the faces. The problem for aquamarines is the disturbed proportions in the pavilion-crown relationship. Insufficient depth of the pavilion leads to the appearance of a “window” effect in the cut stone, when when viewed from the site, the surface on which the stone is located is visible. The excessive size of the pavilion part is inconvenient for fastening in the product, and, as a rule, is not economically profitable. You are overpaying for excess weight. There are exceptions, when a cut stone combines a low pavilion and a pronounced play of light on the edges; they are considered advantageous for the buyer, since they look larger than they actually are, and are more profitable in cost. For example, an 8 carat stone looks like 10 carats, but costs per carat like 8 carats. Such specimens are said to have a “large face.” Such aquamarines rarely appear on the market and are sold out quite quickly, since they are more of a lucky chance for the buyer than a constant value.

Place of Birth

There are aquamarine deposits in a number of countries. Among them are Brazil, Pakistan, Afghanistan, Ukraine, Myanmar (Burma). African countries are also sources of aquamarines: Madagascar, Namibia, Nigeria, Mozambique. Among the Russian aquamarine deposits, we can highlight the famous Sherlova Gora, which is located in Transbaikalia. Aquamarine samples from Volyn, Ukraine have collector’s value. This deposit of beryl and topaz is considered to be mined today, however, single Volyn beryl in crystals and cut from stockpiles or private collections sometimes appear on the market. Crystals of transparent Volyn golden and greenish-yellow heliodors are very beautiful; they have a characteristic elongated shape and a natural surface with etching figures. After refining, such beryls acquire an aquamarine blue color. Vietnam also supplies natural aquamarines to the market; their peculiarity is a rich bluish color, but the purity is low, almost all the raw materials are fissured. Once upon a time, top blue aquamarines were mined in India, but today there is almost no mining. If we talk about aquamarine, we cannot ignore the deposits in Pakistan and Afghanistan. These countries are the birthplace of luxurious aquamarine crystals: of the correct crystallographic form, in a perfectly preserved parent rock – a real miracle, a mineral collector’s dream! However, in these deposits there are no aquamarines of saturated blue colors; all the stones are quite light. Most stones on the international market today are still of Brazilian origin, although African aquamarines from Mozambique and Madagascar are gaining popularity.

How to distinguish an aquamarine from a fake

Since aquamarine stone is very popular, imitations and fakes are also common. It is imitated with glasses (so-called pastes), glass ceramics, synthetic materials, for example, synthetic spinel, YAG, GGG. In order to distinguish aquamarine from imitations and fakes, you need knowledge of gemology and at least a minimum set of gemological equipment: a magnifying glass, a refractometer, a polariscope. Glass and glass ceramics are revealed by the presence of bubbles in the stone when viewed with a 10x magnifying glass. The presence of numerous micro-cracks on the edges of the faces indicates the high fragility characteristic of glass. Glass can also be distinguished in a polariscope: in polarized light, aquamarine will show a picture of an anisotropic substance (when rotated 360 degrees, the stone will darken and lighten 4 times), and glass will show a picture of an isotropic substance, or anomalous anisotropy (dark lines are beams). You can also check the hardness. Aquamarine will not be scratched by a steel blade, but scratches will remain on the glass. But we do not recommend this method.
You can distinguish natural aquamarine from synthetic spinel and other synthetics using a refractometer by measuring the refractive index of the polished face. For aquamarine, the refractive index will show values ​​in the range of 1,57-1,59, the characteristic birefringence is 0.005. For synthetic spinel and YAG this value is much higher. In the photo: IGL expert opinion on natural aquamarine Aquamarine can be similar to other stones of blue and dark blue colors: blue zircon, topaz, and rarely, light tourmaline, sapphire, diamond. These stones can also be visually distinguished from aquamarine. Zircon and diamond are distinguished by high dispersion. Topaz has a cooler and richer blue hue. In any case, if you have any doubts about the naturalness, we recommend contacting a reputable laboratory where you can order a certificate or expert opinion. Please note that the laboratory will most likely not determine whether the stone has been refined or not, but will determine its natural origin and indicate the main characteristics of the aquamarine. In the photo: Certificate (report) for aquamarine from AGL laboratory

Price

  • 5 carat copy – about 200 dollars
  • Sample weighing 10 carats – 240-250 dollars
  • 15 carats and above – from 260 dollars

With a further increase in weight above 15 carats, the price does not increase.

It may seem to you that such prices are too high for aquamarine, but please note that the prices are indicated for stones without an additional greenish tint, that is, pure blue. The largest share of aquamarines on the market are light greenish blue stones; they are approximately 1,5-2 times cheaper than medium blue.
The presence of cleanliness defects (cracks, inclusions) in a copy reduces the cost to 50-80%.
European cut aquamarines cost at least 10-15% more than the listed price. If the quality of the cut is low (obvious asymmetry, violation of proportions, the presence of a noticeable “window”, too deep pavilion, disproportionately high crown), stones are usually sold at a discount of up to 20%.

We will also answer the question: is natural aquamarine jewelry a precious stone or a semi-precious one? There is no consensus on this matter, the answer depends on the coordinate system in which you view the stone. According to the Law on Precious Stones and Precious Metals adopted in our country, aquamarine is not included in the approved list of precious stones, and it can be considered semi-precious. If you look at aquamarine from the point of view of the global gemological community, it is considered a precious stone on a par with other gems. According to the classification of Melnikov E.P. aquamarine is a second order gemstone. We talk more about classifications and gemological concepts in this article. You can select and buy aquamarine in the catalog.

The beauty of the world of jewelry has attracted more than one generation of lovers of natural jewelry. Throughout this period, people are faced with the same question: how to distinguish a fake from a real gemstone? Even in ancient times, craftsmen successfully replaced precious stones with various imitations, finding them not only among natural, cheaper analogues, but sometimes even replacing them with simple glass.

Aquamarine is a popular natural stone that is often tried to be imitated. This time we’ll figure out how to distinguish an aquamarine from a fake.

About imitation natural stones

Considering that the art of creating counterfeit jewelry has successfully developed over many centuries, it is not surprising that it has advanced significantly. Modern jewelry techniques make it possible to “ennoble” lower-grade natural minerals in various ways so that they do not differ from more expensive ones, using annealing, crack filling, irradiation, and surface coating.

The production of synthetic analogues is now carried out on an industrial scale. Moreover, thanks to the achievements of modern technologies, they are not only indistinguishable in appearance and have full compliance with physical characteristics, but sometimes even surpass natural ones in quality. However, it should be noted that natural minerals are always valued much more expensive than artificial ones.

Buyers often have to deal with multiple attempts to pass off artificial stones or ordinary colored glass as a gemstone. Therefore, you should have at least the necessary minimum knowledge so as not to become a victim of deception.

Natural aquamarine and its features

Aquamarine belongs to the category of semi-precious stones and is a type of beryl. It has a soft greenish-blue color. The intensity of the color may change if it is exposed to direct sunlight for a long time.

The properties of the stone include lightness and fragility with relatively high hardness (about 8 on the Mohs scale).

There is an opinion that aquamarine can give courage and self-confidence to people, and is also a talisman of marriage and love relationships. Therefore, for many it can be very important to have a talisman made from a natural mineral, and not a fake one.

As for fake aquamarine, it is almost impossible to find artificial aquamarine. Since it is a semi-precious stone with a relatively low cost, the production of its artificial analogue becomes economically infeasible. This is a rather labor-intensive and complex process that does not justify the production costs at all.

But this does not mean that they are not trying to counterfeit the stone. Spinel, glass and even plastic are often passed off as aquamarine.

How to distinguish the original by color

The color palette of aquamarine is in the spectrum of blue or turquoise-blue, which is commonly called celadon. But its shades may be slightly yellowish or greenish, and in individual specimens a zonal distribution of color may be observed. A unique feature of this mineral is the ability to change color when the angle of inclination changes.

Using neutron irradiation, it is sometimes possible to achieve the natural color of aquamarine, which is bluish, in pink or colorless beryls. However, under the influence of temperature, a reverse color change occurs quite quickly.

Determination by physical characteristics

Like many other natural minerals, natural aquamarine is characterized by the presence in its structure of various inclusions of natural rocks that simply cannot be found in fakes.

Some minerals may have white inclusions, which jewelers call snowflakes or chrysanthemums. Such features are characteristic only of natural stone. When you see them, you can rest assured that this is a product made from natural material, and not a fake “souvenir”.

The authenticity of a stone can be determined by physical characteristics such as density and refractive index. If they are in the range of 2,75 – 2,9 g/cm³, the first one, and the second one, respectively, 1,56 – 1,6, we are not looking at fakes.

Difference from similar colored gemstones

When wondering how to distinguish natural aquamarine from those similar in color, you should decide on analogues of minerals that exist in nature, which closely resemble it.

Among similar stones, which at first glance do not differ from ours, we can highlight the following:

You can distinguish topaz from aquamarine by the more characteristic shine and play of light in the facets of the first. Blue topaz is often cheaper than aquamarine, so unscrupulous sellers pass it off as a sea green mineral.

If we compare it with zirconium, the latter stands out for its pronounced birefringence. Raising it to the light, you can see a peculiar bifurcation of the edges.

It differs from blue sapphire in its refractive index, which can be measured with a special refractometer. In sapphire it is much higher.

Difference from cheap fakes

Considering the absence of synthetic analogues on the jewelry market, remember that if you come across a product that says “artificial aquamarine,” this can only indicate a fake. In such imitations, simple glass or spinel is most often used.

  • Unlike natural stone, all glass imitations feel warmer to the touch . It is enough to touch such a stone, holding it with tweezers, with your tongue. If it remains cold, this is a natural aquamarine; if it becomes warm, it is a fake.
  • Natural stone always has small flaws : foreign inclusions, air bubbles. It won’t be perfectly smooth.
  • Natural aquamarine is completely transparent , It has glossy , not oily shine .
  • Its shade will not be flashy .
  • As already mentioned, a real mineral changes shade at a certain angle of inclination . This property is called pleochroism.

What determines the value of a stone?

Regarding the cost of aquamarine, one should not forget that its price depends on the degree of saturation of the color of the stone. The higher it is, the more expensive the mineral. But the properties of the stone are completely independent of its color. Paler in color, less vibrant varieties have the same properties as their brighter relatives.

Considering that aquamarine is a fairly valuable stone with various unique properties, it is understandable that many people want to purchase jewelry with a natural mineral. More than one generation of scammers has been trying to profit from the gullibility and ignorance of ordinary buyers who want to purchase a beautiful piece of jewelry inlaid with aquamarine at a temptingly low price, but cannot distinguish real from fake. Now you know how to do it.

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