Diamonds cut with Excellent to Good proportions allow a maximum amount of light to be returned to the observer and thus have more brilliance and fire.		A diamond with a deep pavilion will appear dark in the centre of the diamond due to light leakage from the pavilion. Diamonds with a make grading of Medium to Poor will appear like this.		A spread fisheye diamond with a shallow pavilion creates a white circle at the edge of the table when looking down on the diamond. This is actually the reflection of the girdle at the edge of the table. Diamonds with a make grading of Medium to Poor will appear like this.

With the advent of new technology, polished diamonds can be measured very accurately and quickly using laser imaging technology. These measurements are the physical dimensions of the diamond and include all mm, percentages and angles of the diamond that are listed on the majority of diamond grading reports.

Sarin Diascan

As stated previously there are no universally accepted make parameters for round or fancy cut diamonds.

The GIA make parameters for rounds are now becoming the world standard, although all diamond grading laboratories have their own versions of what they consider to be the best and worst make parameters.

All round diamond make parameters on the diamonds.co.nz database are graded using the GIA Facetware program and are measured using laser imaging technology. Further Information on the GIA Facetware program can be found at www.gia.edu

Rounds on diamonds.co.nz are classified as Excellent, Very Good, Good, Fair and Poor

Fancy cuts are a very complex issue and diamonds.co.nz now uses the Accredited Gem Appraiser system developed by David Atlas to differentiate and identify the make of Princess, Radiant, Emerald, Marquise, Oval and Pear shape diamonds listed on the database. More information can be found at www.gemappraisers.com

diamonds.co.nz endeavours to purchase fancy shapes of the best make possible with an emphasis on symmetry and polish.

Fancy shapes on diamonds.co.nz are classified as Ideal, Premium, Fine, Average and Poor.

Ideal and Premium are very strict grades and as with Excellent in rounds. Average is a good commercial make. Sometimes diamonds can be listed with a Poor make on the database. The main reason is because of very thin girdles – this can push a diamond into Poor while the rest of the parameters are in the Ideal to Fine range.

Please click here to view a chart outling the make parameters used to allocate the above make grades for diamonds.co.nz fancy shape diamonds.

Please note that the GIA does not allocate make grades to any fancy shapes – they list Polish and Symmetry grades only. Gem Appraisers are not connected to GIA in any way.