Fancy Color Diamonds
The planet’s most valued gems are fancy color diamonds.
ABOUT FANCY COLOR DIAMOND
Gem diamonds in GIA’s D-to-Z range usually decrease in value as the color becomes more obvious. Just the opposite happens with fancy color diamonds: Their value generally increases with the strength and purity of the color.
Large, vivid fancy color diamonds are extremely rare and very valuable. However, many fancy diamond colors are muted rather than pure and strong.
1 IN 10,000Only one in 10,000 diamonds has a fancy color.
$71.2 MILLIONIn April 2017, the Pink Star diamond, 59.60 carats, became the most expensive gem ever auctioned.
HOPE DIAMONDThe 45.52-carat Fancy Deep grayish blue Hope Diamond is the world’s most famous gem.
FACTSMINERAL: Diamond CHEMISTRY: C COLOR: All colors REFRACTIVE INDEX: 2.42 BIREFRINGENCE: None SPECIFIC GRAVITY: 3.52 MOHS HARDNESS: 10
WHERE IT'S FOUND
There are a number of processes used to alter the color, apparent clarity, or improve the durability of gems.
Some gemstones have synthetic counterparts that have essentially the same chemical, physical, and optical properties, but are grown by man in a laboratory.
Any gem can be imitated—sometimes by manmade materials or by natural materials chosen by man to impersonate a partic gem.