Diamond Guide

Introduction

There are many misconceptions about diamonds and what makes them valuable; this guide has been written to help alleviate these inaccuracies. The 4 C’s (carat, clarity, cut and colour) are how the industry appraises diamonds, so to put you in the picture the 4 C’s are explained below.

Carat

Diamonds are measured in weight using carat. A diamonds carat weight refers to the mass or volume of the stone rather than its actual size. For example a two carat diamond is not twice the size of a one carat diamond, it is twice the weight.

The weight of one carat is precisely 200 milligrams.

It is worth noting that jewellery with more than one diamond will have a total diamond weight, a total diamond weight is not as valuable as an individual diamond with the same weight.

The larger a diamond is the greater its rarity and cost. For example a two carat diamond is approximately four times the price of a one carat diamond of the same quality.

To help you get more of a feel for the size of a diamond, below we have diamond carat weights converted into approximate millimetre sizes.

Brilliant Cut Diamonds	Princess Cut Diamonds
0.10 Carat = 3.00 mm	0.10 Carat = 2.70 mm
0.15 Carat = 3.40 mm	0.15 Carat = 2.90 mm
0.20 Carat = 3.80 mm	0.20 Carat = 3.20 mm
0.25 Carat = 4.10 mm	0.25 Carat = 3.50 mm
0.30 Carat = 4.40 mm	0.30 Carat = 3.80 mm
0.40 Carat = 4.70 mm	0.40 Carat = 4.00 mm
0.50 Carat = 5.00 mm	0.50 Carat = 4.40 mm
0.75 Carat = 5.80 mm	0.75 Carat = 4.90 mm
1.00 Carat = 6.50 mm	1.00 Carat = 5.50 mm
2.00 Carats = 8.20 mm	2.00 Carats = 7.00 mm

Clarity

Clarity is used to express how visually clean a diamonds appearance is, or how many imperfections it has. These imperfections are known as inclusions, an inclusion is technically anything from a trace of non crystallised carbon to a minute crack within the diamond.

Diamonds are graded for clarity under 10x magnification using a jewellers loupe (magnifying glass).

Clarity is graded using the following scale:-

IF - absolutely free from inclusions, no imperfections visible through a 10x loupe.
VVS 1/2 - very very small inclusions, nearly invisible through a 10x loupe.
VS 1/2 - very small inclusions, barely visible through a 10x loupe.
SI 1/2 - small inclusions visible through a 10x loupe but invisible to the naked eye.
P1 - inclusions immediately evident with a 10x loupe though hard to see with the naked eye.
P2 - large/numerous inclusions visible to the naked eye and affecting brilliance.
P3 - large/numerous inclusions very visible to the naked eye and affecting brilliance.

It should be noted that diamonds that have a clarity of SI 1/2 will show no imperfections to the naked eye. The minimum quality for any diamonds used by Hathaway Styles is SI 1/2; diamonds of this clarity have a fantastic appearance and offer good value for money.

The zoom function on our product pages gives you a good indication of what a diamond looks like under 10x magnification.

Cut

The cut of a diamond confusingly relates to two different things. Firstly cut can refer to shape, so if a diamond is round shaped it is brilliant cut and if it is square shaped it is princess cut. Secondly and more importantly cut also refers to the diamonds proportions, symmetry and polish, which are ultimately what determine how well a diamond radiates from within.

A diamond cutter will cut a diamond to make the best use of light, if cut well light will refract from one facet to another ultimately maximising the visible light at the top of the diamond. A poorly cut diamond may lose light through the sides of the stone or even the bottom, which is no good when you’re looking from above 99% of the time.

The achievement of a well cut diamond may be at the expense of sacrificing a little more of the diamonds weight, which is why bigger isn’t always best. At Hathaway Styles we individually select every diamond only choosing those that offer the greatest appearance through brilliance, scintillation and fire.

Colour

The Gemmological Institute of America created a standardised scale for determining the colour of a diamond. They also have a set of master stones for which you can compare diamonds side by side in order to determine a diamonds colour.

GIA’s diamond colour grading scale
Colourless:- D, E, F
Near Colourless:- G, H, I, J
Faint:- K, L, M
Very Light:- N, O, P, Q, R
Light:- S, T, U, V, W, X, Y, Z

The less colour a diamond has the greater its rarity and expense. A near colourless diamond (particularly colours H-G) looks almost identical to a colourless diamond, but is a lot cheaper. Diamonds gradually become more yellowy once you proceed above a colour H. The minimum colour of a diamond used by Hathaway Styles is H.

Premium Diamonds

Do you desire excellence?

For a diamond to be considered a ‘Premium Diamond’ it must meet our stringent grading criteria, diamonds are carefully reviewed by our gemologists before selection. Only the very best quality grade diamonds are appointed as ‘Premium Diamonds.’

Premium Diamonds simplified:-

• Diamonds are cut by master craftsmen who liberate its fire, scintillation and brilliance.


• Exceptionally rare and valuable colourless diamonds; at least colour F.


• Clean of inclusions to the naked eye, barely visible through a loupe; minimum clarity VS2.


• Each diamond is independently certified by GIA, EGL, IGI or Anchor Cert.