Certification

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.

Laboratories
Carat
Clarity
Colour
Cut
Finished Grade
Fancy Cuts Finished Grade

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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Laboratories

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.

Carat

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

Clarity

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
Loupe-Clean		vvs1	vvs2	vs1	vs2	si1	si2	p1/I1	p2/I2	p3/I3
Flawless	Internally Flawless	vvs1	vvs2	vs1	vs2	si1	si2	p1/I1	p2/I2	p3/I3

Colour

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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Cut

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

Proportion

Finished Grade

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

VERY GOOD- GOOD - MEDIUM - POOR

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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