CERTIFICATE
4Cs of
DIAMONDS
The quality of both lab grown and natural diamonds are assessed using the 4Cs of diamonds.
Cut
A diamond cut refers to how well the stone has been polished. The polish is a pivotal part of how well a diamond can reflect the light.
Clarity
The clarity of a diamond refers to how clear it is - and whether there are any inclusions within the gem.
Colour
Diamond colours are graded by letters and give a representation of whether a diamond is clear, on the yellow side, or a coloured diamond such as blue or black.
Carat
The carat of a diamond is how much it weighs. The heavier the diamond, the higher the carat.
1.
Carat Weight
Many people misunderstand the term “carat” as referring to a diamond’s size, but in fact refers to its weight
1 carat equals 200 milligrams, or 0.2 grams. 1 carat is divided into 100 points, so 0.50 carat is 50 points. Note that even a minor variation in carat weight would mean a considerable difference in cost, so accurate diamond weight is important. In general, weight is often measured into one of thousands of carats and rounded to 0.01 carats (e.g. 1.01cts).
The carat of a diamond directly affects its price, but not in a simple positive ratio. Because high-quality large carat diamonds are extremely rare, the price of diamonds of the same grade in terms of color, clarity, and cut multiplies exponentially with an increase in carat weight. A one-carat diamond is far more expensive than two 0.50cts diamonds of the same quality.
2.
Color Grade
Almost all diamonds are formed with a small amount of impurities, such as nitrogen, boron, hydrogen or other elements, resulting in a certain degree of color tone. Nitrogen is the most common of the mixed elements, and it appears yellowish or light brown in lower quality diamonds. Therefore, in general, the more pure a diamond is, and the closer it is to the colorless diamond, the more rare and valuable it is
D-F：Colorless
Color grade D is the highest color grade. Roughly the top 1% of quality based on color. Color grades E and F have virtually no or undetectable amount of color. Extremely rare and valuable.
G-H：Near Colorless
Slight traces of color that are not noticeable to untrained eyes.
I-J：Near Colorless
Color is slightly noticeable, especially when examined face down.
K-M：Faint to Light Yellow / Brown
Color is noticeable.
3.
Clarity Grade
Flawless (FL)
Observed under a 10x magnifying glass, the diamond has no inclusions or blemishes.
Internally Flawless (IF)
Observed under a 10x magnifying glass, the diamond has no visible inclusions, only visible blemishes that only professional graders can see.
Very Very Slightly Included (VVS1 and VVS2)
Observed under a 10x magnifying glass, the diamond’s inclusions are difficult even for a professional grader to see.
Very Slight Included (VS1 and VS2)
Observed under a 10x magnifying glass, the diamond’s tiny inclusions range from difficult to see by professional graders to easier to see.
Slightly Included (SI1)
The diamond’s inclusions can be easily seen when viewed under a 10x magnifying glass, but most do not affect the front appearance and transparency of the diamond.
Slightly Included (SI2)
Observed under naked eye, the diamond’s inclusions are visible, but most do not affect the front appearance and transparency of the diamond.
Included (I1)
The diamond’s inclusions are clearly visible by the naked eye and may affect transparency and brightness.
Included (I2 and I3)
The diamond’s inclusions are clearly visible by the naked eye, and affect its transparency. Diamania does not sell diamonds at this clarity level.
4.
Cut Grade
Among the 4Cs, cut has the greatest influence on scintillation, brightness and fire of a diamond. If not properly cut and polished, even flawless high-color diamonds would look dull.
The factors of Cut, Polish and Symmetry work together to determine the ideal light reflection of the diamond.
Cut
The scale of each facet or proportion of the diamond. Since the scale of each facet, angles and proportion of every diamond is calculated, it needs a suitable standard size to achieve the best internal reflection and refraction to produce beautiful color beams.
Symmetry
The degree to which each facet of a symmetrical or full-grain diamond is cut neatly, such as whether the shape of the circumference is a perfect circle, whether there is a deformed facet, or whether the table is parallel to the bottom.
The above three factors have five levels in GIA.
The highest is Excellent (EX), followed by Very Good (VG), Good (G), Fair (F), and the worst is Poor (P)
CERTIFICATE
Choosing between IGI and GIA depends on your needs and budget. If you are looking for an economical option for lab-grown diamonds, IGI is a good choice. On the other hand, if you seek the highest quality and international recognition, GIA may be more suitable.
IGI
(International Gemological Institute)
-
Popularity: IGI is the most commonly seen diamond certification organization in the market.
-
Authority: Officially recognized, widely accepted in the industry.
-
Cost-Effectiveness: Certification fees are relatively low, suitable for consumers on a budget.
-
Scope: Primarily applicable to lab-grown diamonds.
GIA
(Gemological Institute of America)
-
Established History: GIA has over 80 years of experience in gemology and is one of the most authoritative international certification institutions.
-
High International Recognition: Its certificates are widely accepted globally.
-
Certification Costs: Fees are higher, typically suitable for high-value natural diamonds.
-
Scope: Focuses on the certification of natural diamonds, providing detailed quality assessments.