Are diamonds rare? 

Yes. Natural diamonds are a finite and rare natural material among Earth’s top 10 rarest natural materials. The number of newly recovered diamonds peaked in 2005, so fewer and fewer diamonds have been found every year since. Over the last 140 years, almost 7,000 kimberlite pipes have been analyzed by geologists, yet approximately only 60 of these were deemed suitable for rough diamond recovery. The annual recovery of all natural diamonds 1-carat and above can fill just 1 exercise ball.
Colored diamonds, called fancy color diamonds, are even rarer, due to the unique geological processes that form them. The rarest hues, such as blue diamonds and red diamonds, can sell for over $1 million per carat due to their exceptional rarity.