Diamond is the hardest natural mineral known, where hardness is defined as resistance to scratching. Roughly 49% of diamonds originate from central and southern Africa, although significant sources of the mineral have been discovered in Canada, India, Russia, Brazil, and Australia. Gem quality diamond may be colorless or occur in any hue including the non-spectral hues of gray, brown and black. Diamond is the only gemstone composed of a single element, carbon. Diamond is the birthstone associated with April. It is also the gemstone associated most with wedding engagements and for the 10th and 60th wedding anniversaries.
Diamonds, The King of Gems [1]: Nineteen hundred years ago Pliny, that erudite old Roman, correctly stated that the diamond is the hardest of all substances. But he is scarcely correct in stating that if placed on an anvil and hit with a hammer, the hammer is shattered and the stone buries itself in the anvil.
New Classifications of Rough Diamonds [2]: De Beers Consolidated Mines, LTD., have recently supplied the Gemological Institute of America with the following classifications now in use by that company in grading rough diamonds at the Dutoitspan, Wesselton and Bultfontein mines.
Pink Diamond Gift to Her Royal Highness Princess Elizabeth [3]: As a wedding gift, Dr. J. T. Williamson presented Her Royal Highness The Princess Elizabeth with a rough 54 carat diamond of a deep pink color which had been found in his Tanganyika mine.