At the International Congress of the World Federation of Diamond Bourses and the International Diamond Manufacturers Association, held in Amsterdam in May '75, a joint committee, recently renamed the International Diamond Council, was appointed with a mandate to establish unity in the normalization of the grading of polished diamonds.
The International Diamond Council decided to start from the following principles:
A set of internationally recognized standards should be developed, applic¬able in the same way all over the world.
Working methods for applying these standards should be normalized too. This is necessary in order to arrive at uniform certificates.
Internationally recognized institutes, which will apply the accepted stand¬ards and methods, have to be set up.
As a result of several meetings and discussions of the International Diamond Council in 1975, 1976 and 1977, a first document on the standards as well as on the working methods was drafted in July '77, namely the "Proposal for Normalizing the Description of Diamonds".
In March of the same year, an international series of colour masterstones and corresponding denominations were accepted in agreement with the CIBJO.
In May '78 the basic principles of the standards, called the "International Rules for Grading Polished Diamonds", were proposed for ratification at the 19th Congress of the World Federation of Diamond Bourses and the International Diamond Manufacturers Association in Israel. They were unanimously approved.
The present document is an updated version of the rules, approved in 1995, with amendments based on the remarks and suggestions of the several organizations. All rules approved at the World Congress in Israel are marked "IR May '78" (international rule May '78).
Note: Since the 1995 edition the markings "IR May 78' have been deleted, since they were of historical interest only.