Diamond quality factors-part-2

colour

The nuance of color can greatly affect the value of a diamond. Two diamonds have the same clarity, weight, and cut diamonds, and only the difference in color can make their value very different. Even very subtle differences can make a dramatic difference in the value of diamonds.

Diamonds come in many colors. The general color range of diamonds actually refers to colorless to light yellow or light brown. Colorless diamonds in this color range are the rarest, so they are also the most precious. Within the general color range, other diamonds also have corresponding grading and pricing standards.

In the GIA laboratory, diamonds will be compared with round brilliant diamonds called colorimetric stones under strictly controlled conditions to grade the color of the diamond.

Some diamonds emit visible light when exposed to ultraviolet light (UV). Although it cannot be seen with the naked eye, ultraviolet rays are everywhere. Sunlight contains ultraviolet rays. Fluorescent lamps can also emit ultraviolet light. Under the right conditions, you can see fluorescence in approximately 35% of gem-quality diamonds.

Blue is the most common fluorescent color in gem-quality diamonds. In a few cases, the fluorescence can be white, yellow, orange, or many other colors.

The strong blue fluorescence can make a light yellow diamond closer to colorless under sunlight. Blue and yellow are complementary colors and can often cancel each other, so blue fluorescence can mask the yellow color of diamonds. If the fluorescence is too strong, it will give the diamond a cloudy or "oily" appearance, thereby reducing its value