Conflict Diamonds
There has been a major breakthrough in the campaign to eliminate the traffic in "conflict diamonds". All of the nations with significant involvement in the diamond trade have agreed on a global certification system aimed at preventing criminals from insinuating contraband diamonds mined in African combat zones into the legitimate supply chain. To supplement this government effort, industry leaders have created a voluntary self-regulation programme.
G.H. Pressley & Sons welcome this important development and are actively supporting the system designed to safeguard our products' integrity. For more information please go to http://www.kimberleyprocess.com/
Choosing a Pressley Diamond
At GH Pressley, we have always offered the finest jewellery to our clients. The purchase of a diamond is a uniquely exciting occasion. Whether it is a engagement, eternity ring or an anniversary gift, you may be assured that our diamonds are of the very highest quality.
All our rings are available in a choice of either platinum or 18ct. white and yellow gold.
The ideal proportions
There are many different shaped diamonds available however, six of these are the most popular. Brilliant or round cut, oval cut, marquis cut, pear cut, emerald cut and princess or radiant cut.
The shape of a diamond is largely a matter of personal preference and won't affect its intrinsic value.
How a diamond is cut is by far the most important consideration. In the hands of a master craftsman, a diamond will make the most of the light, giving it a dazzling brilliance. If perfectly cut, light entering the diamond will be refracted internally from facet to facet before emerging through the top of the stone, producing a dazzling 'fire' that is unmatched by any other gemstone.
Ideal Cut
Cut Too Deep
Cut Too Shallow
Colour variations
Most diamonds appear colourless or 'white' but many display hints of colour caused by the presence of other elements during the stone's formation. These are extremely subtle shades and may go unnoticed to the naked eye.
Diamonds are graded by colour and all the major international laboratories have agreed 23 colour grading.
Only 3 of these are classified as colourless. The closer a diamond approaches colourless, the rarer and more valuable it becomes.
Diamonds with a strong, pure colour are also extremely rare and are called 'fancies'. Amongst these diamonds can be found gems that are pink, blue, yellow, green, orange and even black.
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Colourless |
|---|---|
| D E F | |
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Near Colourless |
| G H I J | |
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Faint Yellow |
| K L M | |
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Very Light Yellow |
| N O P Q R | |
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Light Yellow |
| S T U V W X Y Z |
Clearly a better diamond
Diamonds have distinguishing features called 'inclusions', these develop during the stone's formation. It is normal for minute crystals, clouds and feathering to be found in most stones, even if they are only visible through a microscope. This is all part of a diamond's individual nature.
The clarity of a diamond is also graded by international standard, of which there are seven categories. A diamond's value is determined by the number, type, colour, size and position of these 'birthmarks'. The fewer and less disturbing the inclusions, the more valuable the diamond.
Only a gem free from these internal or external inclusions can be graded as 'flawless' and these are extremely rare.
| FL | Flawless |
|---|---|
| IF | Internally Flawless |
| VVS1 - VVS2 | Very, very slightly included |
| VS1 - VS2 | Very slightly included |
| SI1 - SI2 | Slightly included |
| I1 | Inclusions visible to the unaided eye |
| I1 - I2 | Inclusions obvious to the unaided eye |
Bigger is not necessarily better
The weight or size of a diamond is the characteristic that most people believe is how you measure it's value - this is not the case. Two diamonds of equal size can have very different values, depending on the nature of the cut, clarity and their colour.
One carat weight is equal to one-fifth of a gram and is divided into 100 point increments. So for example, if a diamond is marked as 0.75ct., this means that it is ¾ of a carat in weight or, 75 points.
In addition, when mining diamonds, very few will create a stone that will weigh more than one carat. Because of the relative rarity of these large stones, a 2 carat diamond will be worth more than double the value of a 1 carat diamond of similar cut, clarity and colour characteristics.
| Note: Carat is a measurement of WEIGHT, not SIZE and so the overall diameter(mm) could differ slightly larger or smaller even though the carat weight is correct. | |||||||||
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| CT. | 0.25 | 0.50 | 0.75 | 1.00 | 1.25 | 1.50 | 2.00 | 2.50 | 3.00 |
|---|---|---|---|---|---|---|---|---|---|
| MM. | 4.0 | 5.0 | 6.0 | 6.5 | 7.0 | 7.5 | 8.0 | 8.5 | 9.0 |
Note: Images not to scale. Diamond pictures are shown for comparison purposes only. Actual size can vary depending on your screen resolution, monitor size, etc.