Precious Diamonds  - Quality diamonds and custom diamond jewelry
The C's: Color

Most diamonds contain some hint of color. This is caused by the presence of nitrogen in the earth where they formed. Color grading for most diamond is done on a scale of D to Z. A diamond with more color than a Z is a ‘fancy colored diamond’ and could be a different color like pink or blue. These ‘fancy colors’ are not graded on the same scale.

Diamonds in the D-Z scale are graded face-down, viewed through the side of the pavilion. This is because shape and cut quality both influence how light gets in and out of the diamond; grading face-down allows for a neutral assessment of body color. The brilliant cutting style is most efficient for returning light, so a round brilliant or princess may show less apparent color face-up than a step cut like an emerald or asscher.

High Performance Diamonds have superior brightness through cutting standards

The world’s best diamonds are sent to the Gemological Institute of America (GIA) and American Gem Society (AGS). These labs employ strict and consistent standards. Diamonds with AGS and GIA reports command a higher premium and hold their value better than diamonds from softer labs. We recommend AGS & GIA certified diamonds in the D to I color range.

"Super Ideal Cuts" appear whiter when viewed face up or when set in a jewelry setting.

Diamonds cut to the highest level of light performance have critical angles and precision-cutting so light gets in and out with the greatest intensity. "Super Ideal Cut diamonds appear far more colorless than their laboratory cut grades. Only a fraction of the world’s diamonds have such cut quality; they are rare enough that most people have never even seen one. When buyers are considering such cut quality we urge them to dismiss preconceptions and find the “perfect” diamond in a range of color that fits preference and budget; since diamonds of several adjacent color grades will be indistinguishable from one another. Below is a Ray-Tracing Example. Light getting in and out of the diamond does not illuminate body color (Super Ideal Cut) the way light trapped inside the diamond does (poorer cut).

diamond ray tracing example perfect cut stones


HRD Diamond High Council of Europe
McDonnell Diamonds LLC
99 Pine Hill Road #648
Nashua, NH 03063 USA

011 353 1 671 0055 (IRL)
Federation of Jewellery Manufactures of Ireland

© McDonnell Diamonds LLC: Some content used with permission.