When making jewelry that uses a number of gemstones, acceptable ranges for beauty and tone of color are established, and material that falls within those ranges is incorporated. Slight variations in tone levels are unavoidable. Since gemstones are products of the forces of nature, any decisions, such as the matching of rubies for a pendant and earrings, must be made under the assumption that there will naturally be differences.
Professional jewelers give serious thought to the judgment of whether defects are present. A black inclusion directly below the table is an unpleasant defect. Similarly, cleavage in the girdle area is a defect with a negative impact on durability.
Among gemstones that are beautiful and without defects, large size means higher quality. At 0.5 carats, the price of a D-color, Internally Flawless (D-IF) diamond is more than double that of a G-VS2. Given the cost of purchasing a 0.5-carat D-IF, I personally would look for a beautiful one-carat-size diamond with no defects. The essence of gemstones in jewelry is their beauty, not the pursuit of a range grade. The rarity of a particular grade and the rarity of a gemstone that is beautiful and without defects are totally separate matters.
The essence of gemstones’ quality lies in their imperfections. These imperfections give gemstones their individual character and speak to us of their charm. It is for this very reason that people through the ages have loved gemstones. We cannot expect perfection in gemstones. Instead, it is a matte of recognizing what is “imperfect, but beautiful and without defects.”