The most rare and scarce it is, the most expensive it gets. More specifically the diamonds that were born billions of years ago are very rare since just very few of them endured their trip from the depths of the earth to its surface. You will be surprised to know that besides the growth in the field of industrial diamond excavation during the last years, only 350 tons of diamonds have been excavated from the beginning of their history of excavation till the late 1980's.
Here we must point out that less than half of this
quantity was suitable for use by the jewelry business
and then again only a small percentage of this half
quantity of the total world production of diamonds,
reaches after being cut, the size of the "head"
of a match.
These small quantities of industrialized diamonds and gem quality diamonds are not at all easy targets in terms of excavation, even if today's most advanced equipments and means of excavation are being used. It has been estimated that an average of 250 tons of rough raw material, will give after the cutting process, a polished diamond of approximately 1,00 ct size.
THE MOST IMPORTANT ROUGH DIAMOND CUT CENTERS IN THE WORLD ARE: INDIA, ISRAEL, ANTWERP, NEW YORK