There are a few factors that make some diamonds stand out.
Specifically, colored diamonds are often worth large sums of money. They are
rare, especially when they are naturally colored as opposed to being colored in
a laboratory. Besides clear/white-colored diamonds, some diamonds are mined as
yellow and some are mined as red. Colored diamonds should not be confused with
other gemstones—only one in 10,000 mined diamonds are colored. This makes them
very rare and thus, very expensive. In addition, the rarity of color, the
strength of color, the size of the stone and the shape of the stone can help
determine a colored diamond’s price according to the Natural Color Diamond
Association
.
Rarity and value
Rarer colors, such as red, purple and orange are even rarer
than brown, grey and black diamonds. Some of the rarest diamonds may sell at a
rate of $1,500,000 per carat where as some of the more common colored diamonds
may sell at $2,500 per carat!
Strength of color
A laboratory can measure how strong a color is. Some
diamonds are blends of colors, so a lab would measure how intense one
particular color is. More intensely colored diamonds may be worth more.
Size
Diamonds that are large can be considered rare, but not
always. If one diamond is so large that the color intensity or the colors vary
within the stone, then it may be worth less than a diamond that is equally
intense throughout.
Shape
Some diamonds are hard to cut due to their shape. If a
jeweler chooses to cut a diamond a certain way, then a large percentage of the
stone may go to waste, making the diamond less valuable. But, if the jeweler
decides to cut it another way that avoids loosing material, then that other
shape may be less valuable because that shape is less desirable .This puts the
jeweler in a Catch-22 situation. In the end, some shapes are more valuable than
other shapes of comparable size.