The 4Cs of Diamond Quality by GIA (Gemological Institute of America)
Aktualizováno: 13. 12. 2019
1. Diamond Color - The term refers to the absence of color. The less color in the stone, the more desirable and valuable it is. Many of diamond color distinctions are so subtle that they are invisible to the untrained eye; however, these distinctions make a very big difference in diamond quality and price.
2. Diamond Clarity - Diamond Clarity Refers to the Absence of Inclusions and Blemishes.
Evaluating diamond clarity involves determining the number, size, relief, nature, and position of these characteristics, as well as how these affect the overall appearance of the stone. While no diamond is perfectly pure, the closer it comes, the higher its value.
The GIA Diamond Clarity Scale has 6 categories, some of which are divided, for a total of 11 specific grades:
💎 Flawless (FL) No inclusions and no blemishes visible under 10x magnification 💎 Internally Flawless (IF) No inclusions visible under 10x magnification 💎 Very, Very Slightly Included (VVS1 and VVS2) Inclusions so slight they are difficult for a skilled grader to see under 10x magnification 💎 Very Slightly Included (VS1 and VS2) Inclusions are observed with effort under 10x magnification, but can be characterized as minor 💎 Slightly Included (SI1 and SI2) Inclusions are noticeable under 10x magnification 💎 Included (I1, I2, and I3) Inclusions are obvious under 10x magnification which may affect transparency and brilliance To the naked eye, a VS1 and an SI2 diamond may look exactly the same, but these diamonds are quite different in terms of overall quality. This is why expert and accurate assessment of diamond clarity is extremely important.
3. Diamond Cut - Diamond cut refers to the proportion and arrangement of its facets and the quality of workmanship. The amount of brilliance, sparkle and fire in a diamond is determined by cut. Grades range from ‘Excellent’ to ‘Poor.’
4. Diamond Carat - Diamond carat refers to a diamond’s weight. The higher the carat weight, the more expensive the stone. A metric “carat” is defined as 200 milligrams.Each carat can be subdivided into 100 ‘points.’ This allows very precise measurements to the hundredth decimal place.
Diamond price increases with diamond carat weight because larger diamonds are more rare and more desirable. Because diamond’s value is determined using all of the 4Cs (Clarity, Color, and Cut), not just carat weight, two diamonds of equal carat weight can have very different values and prices.
© GIA (Gemological Institute of America)
GIA is the world's oldest, largest, and one of the most respected nonprofit Source of Gemological Knowledge in the World. GIA’s laboratories provide objective standards in the evaluation of a diamond. GIA is not only a unique source for diamond knowledge, its grading reports inspire confidence wherever they appear. The GIA Diamond Grading Report contains scientifically determined information on diamond shape, color, cut, clarity, carat weight, proportions and finish.
✓ Edgar Grig company works with diamonds which are supported by GIA reports. Our jewellers are qualified not only to obtain a GIA certificates but to explain its contents to the Customers.