Articles by this author

This February, we were offered a very nice parcel of Botswanan rough. The size of the stones ranged from 2.60 up to 4.60 Carats, 42 stones in total. With most of the stones being makeables, thus returning only one polished stone, we were looking at the possibility of cutting about 42 stones with a finished weight between 0.70 and 1.75 Cts .

In a previous article, I briefly touched the aspect of perception in our judgement of numbers. I made the case, that since most diamond professionals first gather their knowledge with round brilliants, that they automatically apply rules for rounds to fancy shapes. This is also true with numbers.

In a round stone, the depth of a stone, measured as a percentage of the diameter, is a direct indication of the spread of that stone. Basically, one could say that a higher depth means a lower spread, while a lower depth indicates a higher spread.

Unfortunately, using well-known and tested procedures for rounds on fancies does not always work, and very often, one could be misled by simply using the rule for rounds on fancies. The depth of a princess-cut is a classic example.

Some time ago, I reported you about our experiences while cutting the first princess-cuts, in order to obtain the new AGS-0-cut-grade.

Last week, we received a first batch of six stones back from AGS. Let me tell you how we experience the grading of AGS.

In the course of this first quarter of 2005, AGS will launch new grading reports for princess-cuts. For the first time in the history of diamonds and grading labs, there will be a cut-grade on a fancy shape.

While we are preparing and cutting some princesses in order to get a 0-grade, we are amazed by the major changes that this new grading report demands. I will try to highlight these here.