Advice 1: How to determine the quality of sapphires

The term "sapphire" denoted a variety of the mineral corundum of all colours, except red (red corundum are called rubies). However, when talking about the sapphire, usually mean the stone is blue. Faceted sapphires are the precious stones of the highest category in Russia, they are equated to monetary values. The definition of quality sapphires are made in the following categories: color, clarity, weight and quality of cut. These parameters must be specified on the tags of the jewelry with sapphires.
How to determine the quality of sapphires

The color of the sapphire is determined by experts gemologists visually, when compared with reference specimens. It is characterized by a combination of hue, saturation and lightness. The main color tone of the stone is a pure spectral blue, valid secondary colors – purple and green. Sapphires are also divided into five categories on the lightness and three categories of color saturation. However, for commercial purposes is usually applied a simplified classification of sapphire in color, which includes only three groups. First - bright blue sapphires; the second - medium-blue sapphires; and the third light blue sapphires.

The purity of the sapphire is also defined visually by the naked eye and with a magnifying glass with 10x magnification. Taken four groups according to the purity. The first is almost perfectly transparent sapphires without defects or with isolated small defects that are visible only under considerable magnification. The second - transparent stones with a few minor blemishes and natural inclusions that are not visible to the naked eye. Third - sapphires with a partial loss of transparency, with defects and inclusions that are very visible even to the naked eye. Fourth - sapphires with a marked or complete loss of transparency, with numerous, clearly distinguishable defects and inclusions (or defects are rare, but very large).

Weight of sapphires are measured in carats (1 carat equals 200 mg). Small stones of 1-2 carats are fairly common. Larger are considered sapphires 5 carats. They are very rare. The cost of 1 carat weight of the stone, depending on its color and purity, can reach $ 4,000.

Main ways cut sapphires – faceted and cabochon. From the facet most common cut is round, but often applied also fancy: "heart", "emerald", "Marquis", "oval" and "pear". Cabochon – a way cut in which the stone is given a round or oval convex polished surface. In this way treated sapphires with a significant loss of transparency and a large number of defects. Cut opaque sapphire cabochon with needle-like inclusions of the mineral rutile (so-called "star" sapphires) allows to identify the effect of asterism – the appearance of moving over the surface of a star with 6 or 12 rays.
The quality and price of the stone is very much influenced by its origin. Considered the most high-quality Kashmir sapphires. They have a cornflower blue color and a silky luster. Since the field in Kashmir is no longer being developed, these stones represent jewelry rare and fabulously expensive. Also valued Ceylon sapphires, which are characterized by less intense light blue color. Siamese sapphires from Thailand are much inferior to them in price. Up to 80% of all sapphires mined in Australia, but these stones are the cheapest because they are very dark, with a greenish tinge, low purity.

Abroad adopted a different system of assessing the quality of faceted sapphires, proposed by the American Gemological Institute (GIA). The correspondence between the Russian and Western systems: a first group of clean – VVS (very very small inclusions), the second VS (very small, small inclusions) – SI (small, but noticeable inclusions), the fourth I (inclusions visible to the naked eye). Keep in mind that natural sapphires, unlike diamonds, are not completely devoid of defects, so the category of IF (clean under a magnifying glass) is unacceptable for them. If the seller offers you the sapphire category IF, or fake, or cultured stone.
Useful advice
In most cases, the tag jewelry with sapphire, you specify only weight, group, color and clarity, for example: "0,55 ct 2/2". The quality of the stone on this information as follows: weight of 0.55 carats (110 mg), stone medium blue, clear, defects are few and visible only at high magnification.

Advice 2: How to determine a real sapphire

Sapphire is a precious stone which is famous for its alluring cornflower blue color due to the connection it iron and titanium. In ancient times they decorated the clothing of priests and noblemen. Sapphire is in demand in our days. How to distinguish a real stone from a fake?
How to determine a real sapphire
Color and internal content on the sapphire like natural stones such as tanzanite and blue spinel. Visually tell them apart is almost impossible. For this purpose there is a special device that measures the refraction of light. It is called Refractometer. With its help determine the authenticity of some precious stones. If you measure the refraction of light sapphire, then the index will be equal to 1, 76, tanzanite and 1.7, blue spinel – 1, 72. After the measurement, be sure to look at the stone in profile. If the stone has the same color top and bottom, it's real.
Sapphire is second in hardness stone after the diamond, so like him jewelry doesn't go with it in comparison. Like the sapphire, and many stones have the deep blue color. But, for example, the spinel is too dark to be with him, to confuse, tanzanite slightly reddish hue, and the aquamarine color resembles an ocean wave.
Natural stone should have a visually distinct natural particles (inclusions). Scammers in large volumes create fake synthetic sapphire, which are much cheaper. In such rocks instead of inclusions of natural character under a magnifying glass you can see the gas bubbles. In these sapphires don't. Forgery can also be particles of flux or copper. And yet, do not rely entirely on their own vigilance. To distinguish natural sapphire from a fake can only specialist.
Sapphire is one of those gems that possess high purity. But the complete lack of inclusions suggests that you are trying to sell synthetic fake. Choosing the decoration with a sapphire, please note, recorded it somewhere in the level IF (purity) of the stone. The fact that he is not defined for sapphires, but if the seller tells you the specific data that it sells natural stone.

Advice 3: How to identify the authenticity of sapphire

Is the advice useful?