When buying and selling gemstones in general, and diamonds in particular, the four qualities that most matter to the value of the stone are Cut, Color, Clarity and Carat Weight. These four attributes are commonly called the “Four Cs.” You should be well-informed about the diamonds, rubies, emeralds and sapphires that you are buying or selling; In order to get happy with your purchase or feel confident you were treated fairly in selling your precious or semi precious gems.
1. Cut: it refers to not just the shape of a gemstone, such as round, emerald cut or heart-shaped, but also how it is cut beneath the top surface of a stone. Antique gems will have a much flatter pavilion than will gems cut in the last decades. The better the cut on the pavilion, the more fire and sparkle, and the more valuable. Most modern gems, are often cut with a top and bottom or in other words with the crown and the pavilion, especially diamonds have the Brilliant Cut in which the facets are cut to reflect the most light back up through the crown.
Gemstones can come in a wonderful variety of shapes such as:
Princess, Rose, Heart, Oval, European, Round, Triangle, Trillion, Emerald, Radiant, Marquis, Octagon, Pear, Asscher, Old Mine or others. Here are some images of various cuts for gemstones.
2. Color: the precious gemstones and diamonds are graded on their color. Colored gemstones such as rubies, sapphires, emeralds, topaz, tanzanite and aquamarines are graded on their color, while diamonds are graded D-Z, with “D” being the most white and “Z” the most yellow.
3. Clarity: makes a great deal of difference in value, it depends on how it is structured and what sort of impurities were caught in the gem’s matrix when it was being formed. Diamonds or other gemstones have not any defects visible under close examination. Gemstones are examined for flaws under magnification. Diamonds are graded using the following criteria:
- Flawless (FL) – No inclusions or blemishes are visible to a skilled grader using 10× magnification.
- Internally Flawless (IF) – No inclusions and only blemishes are visible to a skilled grader using 10× magnification.
- Very, Very Slightly Included (VVS1 and VVS2) – Inclusions are difficult for a skilled grader to see under 10× magnification.
- Very Slightly Included (VS1 and VS2) – Inclusions are minor and range from difficult to somewhat easy for a skilled grader to see under 10x magnification.
- Slightly Included (SI1 and SI2) – Inclusions are noticeable to a skilled grader under 10x magnification.
- Included (I1, I2, and I3) – Inclusions are obvious under 10× magnification and may affect transparency and brilliance
4. Carat Weight: the size of a gemstone as measured by its carat weight has great bearing on its desirability and value. Larger gemstones, especially diamonds, are relatively rare and are of greater value, though a larger diamond can be worth less than a smaller one depending on other factors, such as cut, clarity and color.