Diamonds that exhibit a color other than light yellow or brown, as well as diamonds that possess a more intense yellow or brown than the ‘Z’ color rating, are considered fancy color diamonds. With only one out of ten thousand diamonds possessing a natural color, these types of stones are extremely rare. Depending on the coloration, intensity, and hue of a diamond, color can either detract or enhance its value. Naturally occurring diamond colors include gray, white, blue, yellow, orange, red, green, olive, pink, purple, brown, and black. Red stones are the most rare of the fancy colored diamonds.
Similar to the process for grading colorless diamonds, a diamond’s fancy color is graded by comparing it to master stones of predetermined color. Unlike colorless diamonds, fancy colored diamonds are graded face up. The most important factors in determining the value of a naturally colored diamond is the strength of its color. The value of a fancy colored diamond increases with the intensity of the most prominent hue within the stone.
Natural pink diamonds are the rarest. Uniglo Diamond’s pink lab grown diamonds are identical optically, chemically and physically to their natural counterparts. They are conflict-free and considerably lesser in cost. They are usually available in sizes below 2 carats and come in a color spectrum of fancy pink to fancy deep pink.
Unlike white, yellow and blue lab grown diamonds that attain their color in the growing process, pink lab diamonds get their hue from a post-growth treatment known as irradiation and annealing. Usually lighter yellow diamonds are used to create pink diamonds. The lighter yellow diamonds are showered with electrons and neutrons in the irradiation process, altering the diamond’s crystal structure and creating a new colored centre. Then the stone is heated to help smooth out the alterations created from irradiation with the process of annealing, which ultimately helps achieve the diamond’s finished pink color.
A lab created pink diamond’s cost depends on the intensity of the color. Since the pink diamond starts as a yellow colored diamond, the yellow diamond’s octahedral rough produces shapes like radiant, princess, cushion, asscher and emerald which gets the maximum yield. The clarity depends on its color. Pinks that are fuller in saturation have a lower clarity, while a lower saturated pink has higher clarity.
Natural blue diamonds are quite rare. Uniglo Diamond’s blue lab grown diamonds are identical to blue earth-mined diamonds optically, chemically and physically. They are conflict free and considerably lesser in cost than its natural counterparts. They are grown in sizes smaller than 1.5 carats in the Friendly Diamonds’ lab and come in a range of colors from fancy light blue to fancy intense blue.
The blue color in these diamonds come from the impurity boron. As the diamond grows in the lab, controlled amounts of boron are introduced into the growth cell, which then gets trapped in the diamond’s structure. Once light enters the diamond, the amount of boron that has been trapped will determine the intensity of the blue light that is reflected back.
It takes about ten days in the laboratory to produce enough rough to cut up to 1 carat in size. The boron, just like nitrogen, in the growing process quickens the growth compared to a white diamond. However, it still grows slower than a yellow diamond. Blue lab made diamonds are considerably more expensive than other lab colored diamonds due to the time and effort required to reach the color of desire. The rough grows in a hexa-cubic shape and can be cut into round and cut corner shapes like radiant, cushion, asscher and emerald to yield the maximum.
Natural yellow diamonds are fairly rare. Uniglo Diamond’s yellow lab grown diamonds are identical to the yellow earth-mined diamonds optically, chemically and physically. They are free of conflict and considerably lesser in cost. Friendly Diamonds grows them in a color range that goes from fancy yellow to fancy vivid yellow, in sizes up to 2 carats and in a variety of shapes.
The yellow tint in the diamond comes from nitrogen. As a diamond grows, the nitrogen atoms replace the carbon atom within the diamond’s structure, and when light enters the diamond, the nitrogen reflects back yellow light. In the lab, by controlling the amount of nitrogen in the growing process, the color of the finished diamond can be adjusted. The more nitrogen in the diamond, the more yellow it will be.
It takes about one week in the laboratory to create enough rough to cut a 1 to 2 carat finished yellow diamond. The nitrogen left in during the growing process that gives the diamond its yellow colour in fact helps the diamond grow faster than any other color. Lab grown yellow diamonds are the easiest color to grow and therefore relatively less expensive to other colors. The rough grows in a truncated octahedral shape which offers maximum yield with shapes like radiant, princess, cushion, asscher and emerald.