Whilst diamonds often come with some personal value of sentiment the key to figuring out the “worth” of a diamond often comes down to comparing to other similar gems. Much like with buying a house, in that the price of neighbouring homes can often indicate a rough value, a diamonds value can often be indicative from other similar gems. The one complication with this is that no two diamonds are ever the same, with the following 14 characteristics usually studied to determine an approximate worth.
Certification
The diamond grading report, which is recognised as a full GIA diamond certificate, provides all the relevant diamond details. This certificate is issued for natural diamonds weighing 0.15 carats or more, and provides a full quality assessment of a diamond. Other diamond grading laboratories such as the AGS, EGL and ICI are available to provide a certification but the GIA is the most reputable and adheres to the most strict criteria, therefore naturally attracting a higher valuation.
Colour
A chemically pure and structurally perfect diamond is perfectly transparent with no hue, or colour. However, in reality almost no gem-sized natural diamonds are absolutely perfect. The colour of a diamond may be affected by chemical impurities and/or structural defects in the crystal lattice. Depending on the hue and intensity of a diamond's coloration, a diamond's colour can either detract from or enhance its value. For example, most white diamonds are discounted in price when more yellow hue is detectable, while intense pink diamonds or blue diamonds (such as the Hope Diamond) can be dramatically more valuable. The GIA diamond scale works on a lettered basis ranging from D-Z, with each letter representing a range of colour that is based upon a combination of tone (darkness or lightness) and saturation (intensity). With colourless diamonds the closer it gets to the letter D which represents colourless then the more valuable it becomes. With coloured diamonds the intensity is indicated by adding a prefix to the colour. faint , very light, light, fancy light, fancy, fancy intense, fancy vivid, fancy deep or fancy dark. Coloured stones with an intense classification will attract a higher valuation.
Cut
A diamond cut is a style or design guide used when shaping a diamond for polishing such as the brilliant cut. Cut does not refer to shape (pear, oval), but the symmetry, proportioning and polish of a diamond. The cut of a diamond greatly affects a diamond's brilliance; this means if it is cut poorly, it will be less luminous. The most popular of diamond cuts is the modern round brilliant whose facet arrangements and proportions have been perfected by both mathematical and empirical analysis. Also popular are the fancy cuts, which come in a variety of shapes, many of which were derived from the round brilliant. A diamond's cut is evaluated by trained graders, with higher grades given to stones whose symmetry and proportions most closely match the particular "ideal" used as a benchmark.
Clarity
Diamond clarity is the quality of a diamond that relates to the existence and visual appearance of internal characteristics of a diamond called inclusions, and surface defects called blemishes. Clarity is one of the four Cs of diamond grading. Most inclusions present in gem-quality diamonds do not affect the diamonds performance or structural integrity and are not visible to the naked eye. Like the rest of the Four Cs, clarity’s influence on value is directly related to the concept of rarity. Flawless is the top grade in the GIA clarity grading system with diamonds graded Flawless being free from inclusions or blemishes . Flawless diamonds are very rare, to the point there it’s possible to spend a lifetime in the jewellery industry without ever seeing one. As you might imagine, they command top prices. At the lower end of the scale are diamonds with inclusions that can easily be seen by the unaided eye. The stones that make up the bulk of the retail diamond market fall between the two extremes. They usually have inclusions that are visible only under magnification.
Shape
When thinking of diamonds, many will immediately think of the classic round diamond shape. It’s no doubt that the round brilliant cut is the most popular shape but there are plenty of other shapes available. A diamond’s shape refers to its physical form and each diamond shape is very different, possessing unique characteristics. Even though shape is not a part of the 4 C's of Diamonds, this element will have an impact on the value of your diamond. Since each diamond shape is cut to different specifications, they reflect light differently, giving each shape a unique fire and brilliance.
Fluorescence
When UV light strikes a diamond with fluorescent properties, the stone emits a glow. Most often blue, it can also be shades of green, yellow, white or red. Fluorescence can occur in different intensities. Gemological laboratories like the GIA rate on a scale from "None" to "Very Strong". Sometimes, a diamond’s fluorescence will have no effect on its value, or a big impact in other circumstances. Diamonds with a colour grade of D-F, are de-valued if they have a fluorescent glow underneath a UV light, this is because the fluorescence is seen as a flaw, so the diamond no longer holds the same value. Fluorescent diamonds with a colour grade of I-M are actually sold at a premium. The fluorescent glow of a diamond appears blue, which complimentsthe yellow undertones of an I-M coloured diamond, making it appear whiter. Therefore, an I-M coloured diamond will appear more like a higher quality stonewhen it has a slight fluorescence.
Culet
The culet is the small area at the bottom of a diamond's pavilion. The culet can be a point or a very small facetsitting parallel to the table. Any diamond culet size of medium or smaller will be invisible to the naked eye, and have no negative impact on a diamond's appearance and thus its value. However, if a culet is Slightly Large or larger, it may allow light entering from the crown to pass straight through the culet facet, reducing the diamond's brilliance. This may also make the culet appear as an inclusion, or create a dead area on the diamond where the light is escaping through the bottom, therefore having a negative impact upon its valuation.
Table
Have you ever noticed that nearly every diamond has a flat, square-shaped facet on its top? This flat facet is called the table, and it plays a critical role in a diamond’s appearance. The table refracts rays of light as they pass, directing them to the facets that make the diamond look so sparkly. It is important to note that when it comes to the table, bigger is not always better. If the table on a diamond is too large, the upper facets on the crown don’t have room to disperse light. If the table is too small, there won’t be much light getting into the stone, diminishing its overall brilliance and thus its value.
Carat
The carat is a unit of mass equal to 0.2g and is used for measuring not only gem stones but also pearls. The actual weight of any diamond is one of the key factors in determining its value, for example The Golden Jubilee Diamond at 545.67 carats (109.13g) which is said to be priceless due to its rarity has had estimated valuations of between $4 to $12 million US dollars.
Symmetry
Symmetry refers to how precisely the various facets of a diamond align and intersect. This can include extra or misshapen facets, off centre culets and tables, and wavy girdles. A diamond with poor symmetry may misdirect light that travels into the diamond, sending it off at slightly wrong angles, and thereby reducing the diamond's brilliance. Despite its modest impact on appearance, symmetry has a significant impact on price; a diamond with Excellent Symmetry and Polishmay be priced 10%-15% higher than a diamond with Good Symmetry and Polish.
Polish
Polish refers to the degree of smoothness of each facets of a diamond as measured by a gemologist. When a diamond is cut and polished, microscopic surface defects may be created by the polishing wheel as it drags tiny dislodged crystals across the diamond's surface. Depending on the severity, these defects may disrupt light patterns as the light rays enter and exit the diamond. For diamonds with a polish grade of Excellent to Good, any polishing defects are not visible to the naked eye, and should have no impact on the diamond's overall appearance and thus its value.
Girdle
The girdle is the outer edge of the diamond, where the crown meets the pavilion. The girdle is described according to its width. Often, the width of the girdle varies at different points around the diamond, and is quoted in a range designating the thinnest and thickest point along the girdle e.g. "Thin – Medium". A thicker girdle will add weight to a diamond, thereby increasing its price. Since a thick girdle adds depth to a diamond but not width, a thick girdled diamond will not appear any larger when viewed from the top, despite the additional carat weight. The effect on carat weight and price is minimal, but real.
Depth
The depth of a diamond might also be called the “height”: it is the distance from the table to the culet (the pointed tip) of the diamond. Like with a diamond’s table, jewellers grade a diamond’s depth based on its depth percentage. Depth percentage is the diamond’s depth divided by the width of the diamond. This percentage dictates the overall proportions of the diamond, which in turn directly impact how light reflects off the facets in the stone. Because of this, depth contributes to the diamond’s sparkle in a big way. If a cut is too shallow, light will simply pass through the stone and leave through the pavilion without any reflection. On the other hand, a cut that is too deep will have poor sparkle, both of which have a big impact upon a diamonds value.
Origin
Diamonds, the world's most valuable product, are mined in some of the most poverty stricken areas on Earth. There are certain diamond mining companies and diamond cutters that adhere to a higher level of social, ethical and environmental responsibility. These companies are committed to investing profits into improving the quality of life in these regions. They invest in health care, education, wildlife protection and land regeneration. The diamonds sold by these companies may be valued at a slight premium.
Opmerkingen