5 Essential Characteristics of Gemstones:
The color of a gemstone is its most significant characteristic, and many jewelers consider it to be the most vital evaluation criterion. Gemstones are found in all the colors, one can imagine, Color of a gemstone depends on the following three characteristics: hue, saturation, and tone.
Hue is the basic or unique color of the gemstone. In other words, hue is described as the shade, tint or sensation of a color. While almost all gemstones have some shades of other colors, the most valuable gemstones are those that exhibit a pure color and only ‘slight’ hues of other colors in addition to their primary color.
Saturation is a measure of the intensity or purity of a gem's hue or color. A gemstone that is free of gray or brown hues is considered to be strongly saturated and is more valuable than a gemstone with lower saturation. Saturation often decides the cut of a gemstone. A high-quality gemstone cut delivers an even color throughout the stone and exposes the fewest inclusions.
Tone represents the depth of a gemstone color, ranging from colorless to black. In other words, tone is described as the relative lightness or darkness of a Hue. Gemstone tone is described as ‘light’, ‘medium-light’, ‘medium’, ‘medium-dark’, and ‘dark’. Medium-light to medium-dark tone is considered as the most valuable range.
All the above three characteristics are associated with each other and play a very crucial role in determining the gemstone’s color. The more intense the color, more is the value. This does not mean darker, but intense.
Clarity is a term used to describe the absence or presence of flaws inside or on the surface of a gemstone. A flawless gemstone is rare and usually expensively priced. Most gemstones have inclusions, or tiny mineral flaws, that can be seen under magnification or by the careful eye. A gemstone may have inclusions, cracks, spots, clouds, or any other blemish or imperfection.
Clarity is a key factor in determining the quality and the value of a gemstone. Inclusions not only distract the eye but interfere with the behavior of light in the gem and have a significant effect on brilliance or sparkle. Generally, most minerals contain inclusions and spots but if they do not affect the durability of colored gems then these inclusions or spots will not devalue much for the gems except diamond.
For diamonds, Clarity Grade Scale from F (flawless) to I3 (included 3) is used whereas for other colored gemstones a different grading scale is used. Colored stones have different habits of clarity so that they are classified into three ‘Types’, which are defined as under:
Gemstones are generally hard and durable in nature but due to our day-to-day activities, it is expected that our gemstone jewelry get dirty and soiled. Even gems can be scratched, chipped or dulled if not handled correctly. With proper care, they can last a lifetime and can even be handed down as heirlooms to future generations without losing their shine and sparkle. Organic gems like pearls, amber, and coral require special care because they are porous.