Diamond: The most expensive gemstone in the world

Strongly colored diamonds, called fancies, can be genuinely scarce. About one carat out of every 10,000 sold is a fancy. These shades include yellow, green, blue, orange, brown ("champagne"), purple, gray, black, milky white, pink and red. Red is by far the rarest.There are around thirty-five red diamonds currently known and most weigh under half a carat.

The largest is the Moussaieff Red at 5.11 carats, cut from a 14-carat rough found by a Brazilian farmer and displayed at the Smithsonian in 2003.Per carat prices for natural, untreated red diamonds have so far ranged from about $800,000.00 to $1.9 million which makes this substance the world's most concentrated nonradiological form of wealth. Most of the time these stones are unavailable at any price, though there were reports in 2002 of a new discovery in the Lipetsk region of Russia.

SERENDIBITE, not to be confused with serandite, is a cyan colored stone that comes from Sri Lanka. It boasts an unusually complex formula consisting of calcium, magnesium, aluminum, silicon, boron and oxygen. So far there exist three faceted specimens of 0.35 carats, 0.55 carats and 0.56 carats.

The first two were discovered by rare stone specialist D. P. Gunasekera and purchased by the late Prof. E. J. Gbelin of Switzerland. Was sold for about $14,300.00 per carat. The name comes from the old Arabic term for Sri Lanka, Serendib, as referenced in The Sixth Voyage of Sinbad and elsewhere.