How can you spot diamonds

Recognize real diamonds

It is often not easy to distinguish real diamonds from counterfeit or imitation diamonds. Especially for non-professionals.

Real diamond or mix-up

Colorless, cut stones set in jewelry can easily be mistaken for diamonds at first glance.
Colorless or white diamondslook similar to other clear minerals such as rock crystal, topaz / white topaz, goshenite / beryl or zircon.
It is even more difficult to distinguish between colored diamonds - so-called fancy diamonds in yellow, brown, orange, red, pink / pink, lavender / violet, blue, green, gray and black. Colors that are found in abundance in the world of minerals, so that purple diamonds can be confused with amethyst, for example. Pink diamonds resemble the mineral kunzite, blue diamonds resemble sapphires, or green diamonds can be mistaken for emerald or peridot.

For example, the designation Stolberger Diamant, Auerberger Diamant or Bohemian Diamond can be misleading. These supposed diamonds are actually rock crystal or orthoclase.

The best known Diamond imitations is under the name Zirconia guided. The crystals grown in the laboratory were once intended as a cost-effective alternative to real diamonds, but color-imparting substances were soon added to the zirconia recipe so that colored diamonds and any colored gemstone can be imitated. Rhinestone is also an imitation diamond made of glass.

Differentiation based on the properties of diamonds

The surest way to distinguish fake diamonds from real diamonds is to evaluate the diamond Properties of diamonds represent.
Counterfeits and imitations differ significantly from real diamonds.

  • hardness: The hardness of minerals is given with the Mohs hardness; starting from degree of hardness 1 (= very soft, e.g. talc) to 10.
    The diamond reaches 10 on the Mohs scale, i.e. no mineral in the world is harder than the diamond.
    In order to determine the hardness of diamonds or other minerals, the stone to be tested is usually scratched in an inconspicuous place with a diamond-studded needle. If scratch marks can be seen on the surface, it is not a diamond. Because: Diamonds cannot be scratched by softer minerals, but on the other hand they can scratch other minerals.
    There are hardness scales with reference minerals specifically for determining the hardness of minerals, with which the hardness test can be carried out.
  • shine: The way in which the reflection of light appears on the surface of minerals is called luster. Since the shine of diamonds is so unique, radiant and intense, it has been given its own category, the so-called diamond shine.
    Quartz or rock crystal, for example, has a glass-like sheen and can be identified in a direct comparison.
  • density: The density of diamonds is 3.47 to 3.55 g / cm³.
    Zirconias are with a density of 5.6 to 6.0 g / cm3 much heavier than diamonds.
    To determine the density, the stone must be loosely, i.e. not set in jewelry. The materials of the ring band, chain pendant or earrings falsify the measurement results.
  • colour: The color of diamonds is diverse. In addition to the well-known white or colorless diamonds, there are colored diamonds whose tint is justified by disturbances in the structure of the crystal lattice or the incorporation of foreign elements. Proof of the authenticity of diamonds based on their color is not possible.
  • Line color: The same applies to the stroke color. The line color is defined as the color that arises when a mineral is rubbed over an unglazed porcelain tablet. The fine, powdery abrasion indicates the line color, which is white in diamonds as well as in the similar-looking zirconium or rock crystal.
  • Cleavage: If a diamond is carefully broken up with a splitting tool, it is completely cleavable; the resulting cleavage surface is absolutely flat and smooth.
  • Dispersion: The dispersion is a value that reflects the intensity of the play of colors of gemstones, which is created as a result of the decomposition of white light into minerals. To the layman the name is Fire of diamonds or gemstones are probably much more common. The dispersion of diamonds is 0.044 and is one of the most helpful criteria in determining the authenticity of diamonds.
  • transparency: The property transparency, with which the light transmission is indicated, is not suitable for the identification of diamonds. The transparency of diamonds is transparent to translucent and thus belongs to a number of countless minerals that are also of the same transparency.
  • Diamond tester: A quick and safe way to test diamonds for authenticity is with diamond testing devices. The testing devices are no longer reserved for gemstone institutes. The handy diamond tester for private use allows a quick statement to be made as to whether the stone is a diamond, an imitation or zirconia.

Authenticity tests "to go"

There are numerous tests circulating on the Internet with which diamonds are carried out at home and without specialist knowledge. The methods are simple and promise quick results.

  1. Fog test: If a diamond is breathed on, a fine layer of water from the air you breathe is deposited on the diamond surface. Depending on the speed of evaporation, the diamond is real or a fake. A time of three to four seconds is given as a rough guideline. If the mist evaporates faster on the stone, it is therefore a real diamond.
    A test that diamond appraisers do not approve, as even extremely fine dirt on the stone surface can impair the result and the current value is not meaningful enough.
  2. Heat resistance: Another test suggests checking with heat. The stone to be tested is heated with a soldering pipe and then cooled in cold water. Diamonds withstand the procedure, quartz, for example, shatters.
    Also not recommended, as the test is associated with the potential destruction of a stone.
  3. Newspaper test: According to this, diamonds can be exposed to forgeries by checking to what extent one can recognize the writing of a daily newspaper through a cut crystal. If the writing is legible, it is not a real diamond. According to experts, the test is also invalid, if only because imprecise cut proportions and superficial soiling lead to incorrect results.

Certificates of Authenticity

Certificates from well-known gemological laboratories, which ensure the authenticity of diamonds and other precious stones by means of in-depth analyzes, provide absolute security with regard to the authenticity of diamonds.
The best-known exhibitors include the Gemological Association of America (GIA) and the Switzerland-based Gübelin company.

When buying a certified diamond, the authenticity of the stone is confirmed, as is information on the exact description of the color and purity according to the internationally applicable 4C criteria (color, clarity, cut and carat / color, purity, cut and weight). Furthermore, the weight of the diamond, the quality of the cut (including the symmetry of the proportions in%) and the type of expression of any inclusions are mentioned in the certificate.

Diamonds with a certificate are sometimes slightly more expensive, but should not be underestimated as proof of authenticity and as an investment.

The price of real diamonds

Last but not least is the Price an indication of the authenticity of diamonds.
The decisive factors for the price of diamonds are those 4Cwhich are used in cut diamonds.
Rough diamonds that are still unworked often cost less than diamonds with perfectly worked out proportions and the right cut that brings out the diamond's fire to its best advantage.

In addition to the cut, the 4C conglomerate also includes color, clarity and weight (carat; 1 carat = 0.2 g).
Within these quality criteria there are fine gradations that influence the diamond price. Tools can be used online to estimate the price of diamonds using the 4C. For example, a 1-carat brilliant cut in flawless, highest purity and the coveted blue and white costs around 27,700 US dollars (see: - diamond price calculator). Diamonds with a lower purity, yellowish color and lower weight are correspondingly cheaper.

Diamond testing device - Our recommendation *

See also:
⇒ Diamonds that aren't - fake diamonds
⇒ The most expensive gemstones in the world
⇒ The difference between brilliants and diamonds

⇒ Bank, H. (1992): Diamonds. Pinguin-Verlag Innsbruck
⇒ Bauer, J .; Tvrz, F. (1993): The Cosmos Mineral Guide. Minerals rocks precious stones. An identification book with 576 color photos. Gondrom Verlag GmbH Bindlach
⇒ Medenbach, O .; Sussieck-Fornefeld, C .; Steinbach, G. (1996): Steinbach's natural guide minerals. 223 species descriptions, 362 color photos, 250 drawings and 30 pages of identification tables. Mosaik Verlag Munich
⇒ Pellant, C. (1994): Stones and Minerals. Ravensburger nature guide. Ravensburger Buchverlag Otto Maier GmbH
⇒ Schumann, W. (1992): Precious and precious stones: all precious and precious stones in the world; 1500 unique pieces. BLV determination book, BLV Verlagsgesellschaft mbH Munich
⇒ Schumann, W. (2017): Precious stones and gemstones: all all kinds and varieties; 1900 unique pieces. BLV determination book, BLV Verlagsgesellschaft mbH Munich
⇒ Schumann, W. (1991): Minerals rocks - characteristics, occurrence and use. FSVO nature guide. BLV Verlagsgesellschaft mbH Munich
- - How to tell if a diamond is real

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Last updated: April 28, 2021

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