Diamonds: Some FAQs
What is an "ideal cut" ?
An ideal cut is a specific set of proportions for a round brilliant diamond first proposed
by Marcel Tolkowsky in 1919. Today this term is associated with round brilliant diamonds
that are have a "triple zero" cut grade on a Diamond Quality Document from the
American Gem Society Gemological Laboratories.
What is an AGS triple zero? The proportions are:
- Table diameter: 53 to 57.5%
- Crown angle: 34 to 35 degrees
- Crown heightt: 15 to 16.2%
- Girdle thickness: thin to medium
- Pavilion angle: 41 degrees
- Pavilion depth: 43 to 43.5%
- Culet: very small
- Total depth: 60 to 62%
But the AGS ideal cut grade is not just a question of a diamond's proportions: it also
means the diamond has the highest grade for symmetry and polish as well. Be wary of
sellers who say a diamond without an AGS DQD is an "ideal cut." GIA does not
grade proportions and table and depth percentages alone do not mean a diamond is well cut.
For more information, read Ideal Cuts: A Consumer Guide.
Where do diamonds come from?
Diamonds are mined in many parts of the world, but 80% of the
stones on the market today come from Angola, Australia, Botswana, Namibia, South Africa,
Russia and Zaire. All of these sources might appear to indicate great availability, but
this is not the case. More than 250 tons of ore need to be blasted, crushed and processed
to yield just one carat of rough diamond. If that weren't enough, most of the rough
extracted from the ground is not suitable for gems; only about 20% of all rough diamonds
are suitable for gem cutting.
diamond a good investment?
It depends. Buying diamonds at the retail level is not necessarily a good
investment since the item has been marked up considerably from the wholesale price. The
only way you would ever recover the money spent would be from an insurance claim. However,
buying a stone wholesale means you pay a price much closer to its "actual"
value. Diamond prices have been increasing steadily for about twenty years, so they hold
their value well. But if you buy a diamond with the intention of turning a profit, you
will probably have a difficult time. As the end consumer, think in terms of buying a
diamond for its beauty. And remember that when you are buying a diamond engagement ring,
the most important investment you are making is the lifelong relationship with your
the difference between certified and non-certified diamonds?
Gemological institutes spend a lot of their time
certifying the quality of diamonds based on the Four Cs. A certified diamond is one
accompanied by a certificate from a laboratory ensuring its quality. This is not to say
that a certified diamond is better than one that isn't, it simply means that the one with
the certificate comes with proof of its quality while the uncertified lacks that