THE HOPE DIAMOND – $350 MILLIONS
With a name like that, you would be surprised to know that there is a legend of it carrying a curse. Nothing surprising, as it has wrecked most of its previous owners. It is not simply blue in color due to the presence of boron atoms in it but turns red under ultraviolet light due to the phosphorus content. This 45.52 carats diamond was discovered in the Kollur mines of Andhra Pradesh in India in the 1600s, and got its name from the Hope banking family in London who acquired it sometime in 1839.