Diamond - Carat « BACK
The first C out of 4 Cs of diamonds is Carat .The weight or size of a diamond is measured in carats (ct.).One carat weighs 1/5(0.20gm) of a gram or 200 milligrams and is divided into 100 points.The point unit-equal to one one-hundredth of a carat (0.01 carat, or 2 mg) is commonly used for diamonds of less than one carat.All else being equal, the price per carat increases with carat weight, since larger diamonds are both rarer and more desirable for use as gemstones.
The term carat originates from the Greek and Arabic names for the carob tree - Keration in Greek and Qirrat in Arabic. The dried seeds of the Carob (or Locust) tree were once widely used by trading merchants as counterweights for weighing gold, diamonds, gemstones and pearls due to their relatively consistent weight and size. It is important to note however, that the term "carat" with reference diamonds is different to "karat" which is the value used for the purity of gold.
The Byzantine era used glass pebbles, based on carob seeds, for weighing coins, which weighed in at 196 mg, consistent with the average weight of an individual carob seed. However their use eventually diminished as it was discovered that despite their visual uniformity, the seeds were not actually consistent in weight. Many attempts were made to standardise the measurement of gemstone weight and it was only in 1907, at the Fourth General Conference on Weights and Measures that the "carat" was adopted as the official metric measurement for gemstone weights.
In 1913 the United States officially accepted the 'carat' as the gemstone measurement, and in 1914 the United Kingdom and Europe followed suit. By the 1930s, the majority of the diamond and gemstone industry including surat & mumbai , india had agreed to the standardised measurement, which is still in use today.
While the size of a polished diamond is related to its carat weight, it is important not to confuse carat weight with size, as there are other aspects of a diamond that can affect how large an individual stone actually appears-most importantly, the cut and shape of the stone. Proportions to which an individual diamond is cut, such as table and depth percentages must be taken into account, as shallower stones can appear larger than deeper stones of the same weight. Similarly, diamond shapes can have an impact, as elongated shapes tend to maximise carat weight, making them appear larger than rounded stones of the same weight.
Furthermore, the appearance of a diamond's size can also be affected by how the stone is set in a piece of jewellery, as well the size of the wearer's finger (in the case of rings), therefore it is important to take all of these aspects into consideration when choosing a stone.
Carat weight is one of the fundamental factors in determining the price of a diamond. As a general rule, the heavier the diamond, that is, the larger the carat weight, the more expensive it becomes. Price per carat is one of the best ways to compare the cost of similar diamonds. To calculate this, simply divide the cost of each stone by its carat weight. Because they are more scarce, larger diamonds are in much higher demand than smaller stones and therefore command much higher prices per carat. A diamond that is double the size of another can be up to four times the price. For example, a one carat diamond solitaire ring is nearly always more expensive than a diamond ring made up of smaller multiple diamonds whose total weight is one carat.
Carat weight is the weight of the diamond measured in carats. One carat is divided into 100 "points," so that a diamond of 75 points weighs 0.75 carats. Carat weight is the most obvious factor in determining the value of a diamond. But two diamonds of equal carat weights can have very different prices, depending on their quality. Diamonds of high quality can be found in all size ranges.
The price per carat does not increase linearly with increasing size. Instead, there are sharp jumps around milestone carat weights, as demand is much higher for diamonds weighing just more than a milestone than for those weighing just less. As an example, a 0.95 carats (190 mg) diamond may have a significantly lower price per carat than a comparable 1.05 carats (210 mg) diamond, because of differences in demand.
Total carat weight (t.c.w.) is a phrase used to describe the total mass of diamonds or other gemstone in a piece of jewelry, when more than one gemstone is used. Diamond solitaire earrings, for example, are usually quoted in t.c.w. when placed for sale, indicating the mass of the diamonds in both earrings and not each individual diamond. T.c.w. is also widely used for diamond necklaces, bracelets and other similar jewelry pieces.