Diamonds Forever New Zealand Diamond Engagement Ring Specialist

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Before purchasing a diamond, you should expect to review a copy of its certificate, as this is your guarantee of the quality and value of that diamond.


What's in a Certificate?

A diamond certificate, also called a diamond grading report, diamond dossier®, or diamond quality report, is a report created by a gemologist, or gemologists, who have scrutinised the diamond and placed it under a microscope to analyse its dimensions, cut, colour, clarity, carat weight, symmetry and other characteristics.


DFNZ diamonds are all certified

All diamonds offered to you by 'Diamonds Forever NZ®' have been analysed and graded by an independent and professional gemological laboratory in accordance with the "International Rules for grading polished diamonds" established by the International Diamond Council. (HRD standard).


Allan Woods, an Antwerp Diamond High Council (HRD) graduate and tutor of gemological studies in Auckland has appraised and certified all the stones that are available for you to purchase on this site that have not already been certified internationally by the Gemological Institute of America (GIA) or the HRD.



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These laboratories are known for having the strictest, most consistent and unbiased systems for grading diamonds. Diamonds that are accompanied by these grading reports are the most highly valued in the industry, as their quality is considered guaranteed.


All rings sold on this site come complete with a full independent valuation for yourself and a copy for your insurance company.


The quality grading of polished diamonds can be summarized by what is generally known as the 4 Cs. These are four parameters which bring together all of the properties and characteristics of a polished diamond.



The weight of a diamond is expressed in carats 100 points = 1ct.



The clarity of the diamond is determined by its internal and
external characteristics. The best quality is called "loupe clean". This means that upon
examining the diamond with a loupe (x 10 magnification), no inclusions can be found.

IDC - International Diamond Council (HRD)


Comparison table of various clarity graders
With loupe 10× Measurement with Microscope Naked Eye
Flawless Internally Flawless



The colour of a diamond depends on the presence or more specifically, the absence of colour in the diamond. The majority of good quality diamonds are colourless or near colourless. Diamonds can, however, be found in nearly every colour. Exceptional colours are for example red, blue and pink.


Colour Grades
Colourless Near colourless Faint Yellow Very light Yellow Light Yellow
D E F G H I J K L M N O P Q R S - Z


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The cut is very important in terms of the brilliance of the stone. The
cut is composed of two parts: the proportions and the finished grade.


Good proportions are necessary for the brilliance and "fire" of the diamond. Significant deviations from the ideal proportions make the stone look dull and unappealing.


The proportions are only assessed for diamonds with a (round) brilliant shape. For all other cuts, proportions are measured, but no final evaluation is given, as in this area no international norms exist. The enormous variation in the proportions between the different fancy cuts, make it impossible to judge them according to one ideal.


International Diamond Council (IDC) HRD grades the Proportions:-

Very Good - being the highest equivalent to Excellent / Ideal
Good -being equivalent to Very Good
Unusual - being Fair / Poor/ Promotional


Every diamond laboratory has slight variations of what a beautiful cut diamonds proportions should be. The leading gemology laboratories agree on the following proportions. For the proportion Grade to be termed Very Good (equivalent to Ideal Excellent) they have to fall within certain criteria.

Criteria Very Good
Crown Angle From 30.7 – 37.7 degrees
Pavilion Angle From 39.6 – 42.2 degrees
Table Width From 66 - 53
Crown Height From 11.0 – 16 %
Girdle Thickness Thin & Medium
Pavilion depth From 41.5 - 45%
Cutlet Size From pointed – 1.9%
Total depth From 55.5 – 63.9



Finished Grade


IDC (HRD) standards for the finished grade
Four different finish grades are differentiated:



HRD Grade Equivalent GIA Grade Description
VERY GOOD Ideal – Excellent This range is very strict and combines the best in brilliance and fire
GOOD Very Good This range is balanced between precise proportions and price considerations.
MEDIUM Good Is of a general commercial grade that is good value
POOR Med / Fair / Poor Grades which are priced accordingly

Fancy Cuts Finished Grade

Generally fancy cuts will be termed as "Good-Fancy" on the diamond certificate/valuation.

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