When diamond certificates
were first introduced back in the 1950's most diamond grading reports
were used for the higher quality large diamonds only. Today, diamond
certificates are being used for all quality diamonds and there are
several gem labs from which to choose. Below are samples certificates
from two of the most widely known gem laborites E.G.L. and GIA.
The European Gemological Laboratory
or E.G.L. is the worlds largest gem lab. Established in 1974 E.G.L.
has offices in all the major diamond centers including New York and
Israel. Their reports are more comprehensive than the GIA reports because
they include Crown Height and Pavilion Depth. Like all diamond grading
reports, you will notice the diamond plot showing the location of all
inclusions and blemishes. This graph is very useful for the proposes
of identifying your diamond if it is either lost or stolen.
The Gem Trade Laboratory has
a long history in the diamond industry. When the Gemological Institute
of America developed its grading system for diamonds it started producing
diamond grading reports or certificates as they are referred to today.
As is the practice in most gem laboratories each diamond is graded
by a trained gemologist, then for accuracy the diamond is reviewed
by two other gemologists. This is why on some older certificates you
will see three signatures. Today, the practice is the same but the
certificates are no longer hand signed. It's interesting to note that
even in a gem laboratory the art of diamond grading is still a subjective
one, even highly trained diamond graders will not always agree.
