Tips for stone care

How to distinguish natural zircon from a fake?

Cubic zirconia is often passed off as zircons. The following signs allow you to recognize a gem:

  • A transparent natural mineral is very rare. Such a stone will certainly contain inclusions. Cubic zirconias are characterized by absolute transparency.

Place of Birth

Deposits of gem-quality zircon are quite rare, although it is a fairly common mineral.
The main source is deposits in Cambodia, Myanmar (Burma), Thailand, Vietnam, Sri Lanka, Tanzania and Madagascar. The best blue specimens are obtained by heating the brownish ones, which are of Cambodian origin.
Cut specimens from deposits in the USA, Brazil, Canada, Norway and Australia also come to the market.
In Russia there are finds on the Kola Peninsula and in the Urals.


The properties of the mineral are very interesting; depending on the crystal structure, high, low and intermediate are distinguished. The chemical composition of the mineral is zirconium silicate. The hardness of 6-7.5 on the Mohs scale is sufficient for this natural stone to be framed in jewelry for everyday wear. Characteristic property is strong birefringence, which can be seen as bifurcation of the ribs when viewed through a faceted stone.

Mineral type: zircon

Chemical formula: ZrSiO 4

Optical character: anisotropic

Density: 3,90-4,73 g/cm 3

Luster: glassy to diamond

Refractive index: 1,925-1,815

Color: blue, colorless, yellow, brown, etc.


  • The oldest mineral found on Earth is zircon from Australia, which is 4,4 billion years old.
  • Cut colorless zircons from the Ceylon city of Matara were mistaken for diamonds in Europe until the 18th century.
  • Tiny crystals can be found as inclusions in various gemstones. For example, they are sometimes found in rubies and sapphires.
  • Zircon contains impurities of rare earth metals, uranium, thorium, due to which the gem becomes radioactive.
  • Under the influence of ultraviolet light, the bulk of zircons exhibit a fluorescent effect.
  • This stone is often confused with zirconium metal and cubic zirconia stone, which is also called “zirconium cube”.


Zircons were known back in Ancient Rome. They are mentioned in the treatise “Natural History” by Pliny the Elder. They became especially valued in the 15th-16th centuries, when they first began to arrive in Europe. Heated colorless stones were used as diamonds, which was fixed in their names – Ceylon diamond and Matar diamond. Yellow zircon was called “jargon” or “Siamese diamond”, brown-red – “hyacinth”. Blue Starlite was especially favored during the Victorian era. The famous Tiffany gemologist George Kunz popularized it and coined the name “starlite.”


Zircons are characterized by the use of heat treatment to change color. By annealing brownish crystals, blue, orange, yellow and colorless colors are obtained. An interesting property is that blue shades, reheated in an oxygen atmosphere, become golden yellow. The color of heat-treated samples is usually stable. Some heated orange and yellow zircons from Africa may turn brownish over time.

The healing properties of the stone

Lithotherapists recognize zircon as a universal gemstone. The healing properties of the stone depend on the shade:

  • Bright red colored gems improve appetite and normalize the functioning of the gallbladder and liver. Minerals are able to regulate the functioning of the thyroid gland and improve the functions of the pituitary gland.
  • Hyacinths have the most pronounced medicinal qualities. With their help, the body is cleansed and insomnia is eliminated. Crystals help normalize emotions, promote rapid healing of wounds and recovery from injuries.
  • Blue-hued gems have a positive effect on the functioning of the digestive system.
  • Malakons with a rich brown color help fight respiratory diseases (bronchitis, pneumonia, sinusitis).
  • Transparent stones normalize metabolic processes and eliminate excess weight.

PHOTO of zircon

Photo of a large Cambodian zircon 30,35 ct of excellent rich blue hue

The photo shows a colorless stone, rare in its purity and size, weighing 33,66 ct (Cambodia)

Photo of a natural untreated specimen 9,70 ct, reminiscent of a cognac diamond (Vietnam)

Lot of zircons of various colors from Burma (Myanmar)

Green, yellow and blue faceted specimens

Photo of a ring with zircon – design and execution from Gemlovers

In the photo: yellow zircon cushion shape

Starlits (origin: Cambodia)


In the video: bright blue cut Cambodian zircon

Zircon in our catalog

Large Cambodian cushion zircon 12.81 carats

  • Cleanliness: visually clean
  • Upgrading: heat treatment
  • Cut: cushion
  • Dimensions: 13.94×11.53×8.19
  • Origin: Cambodia

Blue zircon pear cut 3.65 carats

  • Cleanliness: visually clean
  • Upgrading: heat treatment
  • Cut: pear
  • Dimensions: 11.88×7.96×4.28
  • Origin: Cambodia

Natural green zircon stone 4.28 carats

  • Cleanliness: with barely noticeable inclusions
  • Ennoblement: unknown
  • Cut: oval
  • Dimensions: 10.36×8.45×5.87
  • Origin: Tanzania

Pair of blue zircons 11.52 carats

  • Cleanliness: visually clean
  • Upgrading: heat treatment
  • Cut: cushion
  • Размеры: 8.03х9.26х6.93; 8.19х9.13х6.61
  • Origin: Cambodia

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A trip to a zircon deposit in Cambodia – part 1

  • Zircon is an amazingly beautiful stone, called the younger brother of diamond. Fraudsters often use the visual similarity of zircon and diamond to sell jewelry on a “promotion” or “sale.”

    Darkened zircon even imitates other expensive gems – sapphires, topazes, rubies

    But natural zircon itself is counterfeited, replacing the natural mineral with grown cubic zirconia or zirconium, or even glass.

    Crystals can be very similar, but there are enough differences between them that they are not difficult to find even without special equipment and professional skills. A cheap fake often looks more attractive than the original.

    Key moment: synthetic crystals are simply perfect. Possessing excellent transparency, absolutely uniform and saturated color, with a play of light on the edges brighter than that of a natural gem, they are extremely attractive and are not so expensive.

    Properties of natural and synthetic stone

    An artificially obtained crystal has different properties than a natural mineral:

    • different crystal structure (and therefore the degree of hardness and fragility, refraction of a light beam);
    • chemical composition;
    • physical properties.

    It is wrong to focus on the presence of inclusions in the case of zircon: this stone is valued for its purity, and a priori there cannot be impurities in artificially grown crystals.

    When identifying a counterfeit, they focus on basic properties of solids: ability to conduct heat and transmit light, cleanliness, etc.

    Simple tests

    You can recognize a natural mineral and its analogue upon purchase or later at home. There are several simple techniques that will help reveal the artificial nature of the gem:

    • Breathe on the stone: synthetics will fog up, real mineral will not.
    • Different cuts: natural colorless zircon is usually cut with a diamond cut of 57 facets, colored ones – depending on the design, often in a mixed way (diamond top and stepped bottom). This cut reveals all the beauty of the crystal. The counterfeit is made with a significantly smaller number of edges, their edges are slightly rounded, and remember about its ideal appearance – no irregularities, inclusions, or flaws.
    • Hold the stone in your hands: The fake one will quickly gain body temperature, the natural zircon will remain cold.

    • Cubic zirconia and zircon by hardness and light refractive index are almost identical; using these criteria, a non-specialist is unlikely to be able to identify a substitution.
    • Under ultraviolet light a synthetic stone will take on a gray or greenish tint, while a real one will glow blue.
    • Place a stone on any printed text: through a synthetic crystal the letters will be clearly visible, but through zircon you will not see anything.
    • Light transmission capacity is also different: the sun’s ray will pass through the fake without problems, but zircon does not transmit light, creating a blurry reflected spot.
    • If you are interested in the authenticity of zircon in jewelry purchased long ago, pay attention to the shine: natural minerals do not fade over the years.

    In some cases, you can determine whether the stone in front of you is natural or fake, but the most reliable way is to ask the seller product certificate. If there is no document or it seems suspicious, refuse to purchase.

    The low price should also be of concern: zircon is an expensive mineral, the cost of large colorless zircons of proper cut and purity varies in the range of 100-200 US dollars per carat.

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