The price of each diamond having the same weight depends excessively on its degree of clarity. When you are buying them online, make sure you choose the best clarity grade. For example, the price for a D colour diamond with VVS1 clarity will be 28% lower than a D colour diamond with IF clarity.

Diamond colour

Diamond colourThe Diamond colour grading scale

The most desired diamonds are of no colour (D).

The colour-grading scale ranges from letter D to letter Z, with each letter have its nuances, changing from light yellow to brown to grey. We recommend you to buy the diamond symbolized by at least the letter G when buying online.

Diamond Clarity

A diamond may have inclusions, irregularities, and external defects. A diamond with a high degree of clarity does not indicate its beauty nor its superior aesthetics, but rather determines its value and rarity.

The VS2 grade is recommended by Maison Jaubalet's advisors for buying a diamond on the Internet..
Diamond Clarity
FL Perfectly clearNo inclusions or stains of any kind visible to a qualified assessor under 10x magnification
IF internal clarityNo inclusion, only a few spots are visible to a qualified assessor under 10x magnification
VVS1 et VVS2 very very small inclusionsInclusions are difficult to see by a qualified assessor under 10x magnification
VS1 et VS2 very small inclusionsThe inclusions are easily visible under 10x magnification, but can be considered minor
SI1 et SI2 small inclusionsInclusions are visible to a qualified assessor under 10x magnification
I1, I2 et I3 imperfectInclusions are clearly visible under 10x magnification and may affect the transparency and brilliance of the stone

The weight of diamond

0,30 carat4,20 mm2,60 mm
0,50 carat5,20 mm3,30 mm
1,00 carat6,50 mm4,10 mm
1,50 carat7,40 mm4,60 mm
2,00 carats8,20 mm5,00 mm

Always ensure that you get a certificate mentioning the weight with your online purchase of diamonds.

The weight of a diamond is expressed in carats, the word coming from the carob tree whose constant weight seeds were originally used (one carat = 0.2 grams). A large cut makes a diamond rare. Although it only weighs twice as much, a 1.00 carat stone is statistically much more difficult (and therefore rare) to find than two 0.50 carat stones. It is partly because of this that a 1 carat stone is worth on average 4.2 times the price of a 0.50 carat stone of equal quality, even though it weighs only twice as much.

The fluorescence of a diamond

When a diamond is kept under an ultraviolet light it should have a weak fluorescent reflection, if the diamond remains dark it is not fluorescent. When the fluorescent reflection of a diamond is strong, some general aspects of the stone can be modified under certain lighting, thus depreciating its value.

Five diamonds under a UV lamp show no fluorescence on the left and very strong fluorescence on the right:

The fluorescence of a diamond
«none» ou «nil»for the absence of fluorescence
«very slight»for very slight fluorescence
«slight» ou «faint»for slight fluorescence
«medium»for an average presence of fluorescence
«strong»for strong fluorescence
«very strong»for a very strong fluorescence

Buying a diamond online,
Jaubalet Paris advise you to buy a diamond without any fluorescence or possibly “very slight”

The polish of a diamond

very goodvery good

When buying a diamond online, check its polish. The quality of the polish can be determined by observation of:

  • The absence of a slight or strong polishing streak.
  • The presence of scratches or scuffs, if too important are mentioned in remarks.

When buying a diamond online,
Jaubalet Paris advice you not to go below very good.

The Diamond symmetry

When buying a diamond online, check its symmetry

The symmetry could be estimated by the observation of:

  • The right combination of facets
  • The symmetry of the facets

The presence of important additional and naive facets (evidence of the rough shape)

  • The centre of Colette
  • The centre of table

Jaubalet Paris advise you not to choose a diamond below very good symmetry.

The Diamond symmetry

Example of defects in symmetry

very goodvery good

The Diamond Table

Brilliant diamonds with elegant beauty are with table proportion between 52% and 62%, for weight above 0.50 carat.

Jaubalet Paris advise you not to choose above 62%

The Diamond Table