The World's Rarest Gemstone

Vivid Violet-Blue Tanzanite

Some minerals are so rare that only a handful of specimens are known to exist worldwide. A few of these very rare minerals, such as painite, have even been found only in gem-quality specimens. Up until 2005, there were only 25 known specimens of painite in the world, and only a few of them were ever faceted. Other rare gems include jeremejevite, taaffeite, poudretteite and serendibite; all of which are some of the rarest in the world with regard to occurrence. Even well-known gemstones like tanzanite, jadeite and alexandrite are considered by most to be in the top rare gems list. But in the international gem trade, the rarest gemstones are not those with the least occurence known to man, but instead, the rarest stone titles are awarded to those that draw the highest price per carat at auctions such as Sotheby's and Christie's.

Red Diamond

Based on this criterion, certain colored diamonds are the rarest gemstones in the world, particularly vividly colored natural diamonds that are pink, blue, yellow or green. Among the colored diamond gemstone family, the rarest color variety of of all is the red diamond. In fact, there are only perhaps 20 to 30 red diamonds known to exist, and most weigh less than half a carat.

The 0.95-ct Hancock Red Diamond

A new price record was set in November 2007 at Christie's in Geneva. A ring containing a rare 2.26-carat purplish-red diamond sold for $2.6 million; about $1.15 million per carat. Later in 2015, a 12.08-carat vivid blue diamond claimed the newest world record, fetching $4 million USD per carat. The $4 million USD price tag beat the previous record by over $1 million USD. But the most recent record-breaker for most expensive jewel goes to the 14.62-carat Oppenheimer Blue Diamond, which sold at Christie's in Geneva for a whopping $57.5 million USD.

Moussaieff Red Diamond

Some colored diamonds, such as blue and yellow diamonds, are colored by trace amounts of impurities. Yellow and champagne diamonds are colored by nitrogen, and blue diamonds by boron. However, red and pink diamonds are not colored by impurities; rather their color is the result of minute defects in the crystal lattice. The highest price paid for an orange diamond, was for a 14.82-carat stone known as 'The Orange', which fetched almost $2.4 million USD per carat.

Other Record-Breaking Rare Gemstone Types

Other notable record-breaking rare gems include more red gemstones, including a 15.04-carat Burmese ruby, known as the 'Crimson Flame'. In 2015, a private buyer in Hong Kong paid $18 million USD for the remarkable ruby.

Faceted Burma Ruby