How to Determine the Weight of a Diamond?

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The weight of a diamond is one of the 4 criteria used to estimate the quality of a diamond. It is always noted on the diamond's certificate of authenticity. But how can you obtain the weight of a diamond that does not have a certificate from one of the main international gemological laboratories? We explain what the carat is and how to easily calculate the weight of a diamond in carats. Our customer service is available free of charge to estimate your jewelry.

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Understanding the concept of carat

Carat weight is different from weight in grams, just as it is different from diamond dimensions. Two diamonds can indeed have the same carat weight but different dimensions. Dimensions are determined by the height of the diamond, the width of the diamond, and measurements of its various parts (such as the girdle and table). The carat is therefore a unit of mass, not a unit of volume. The carat is a unit of weight used to determine the weight of diamonds as well as other precious stones. It has been used for a long time but was only standardized at the beginning of the 20th century: before that, each city trading diamonds established its own carat reference. While the carat could equal 0.2057 grams in Holland or 0.1972 grams in Italy, today it equals 0.2 grams (or 200 milligrams) everywhere in the world. 1 carat = 1 ct = 0.20 gram. Be careful, you must differentiate the carat as a unit of diamond weight from the carat of gold alloys. 24-carat gold does not correspond to gold weighing 120 grams! We speak of 24-carat gold when the alloy contains 99% pure gold. Similarly, 18-carat gold contains 75% pure gold. 14-carat gold and 9-carat gold are therefore lower quality gold.

The concept of points to make the carat more precise

At the beginning of the 20th century, gemologists calculated the weight of a diamond in carats and fractions of carats. The weight of a diamond could thus be noted as follows: 1 + 1/2 + 1/8 carats. More recently, gemologists needed to be more precise in estimating diamond weight and therefore divided the carat into 100 points. Each point equals one hundredth of a carat. The introduction of the concept of points enabled gemologists worldwide to obtain a precise weight for each precious stone to the nearest hundredth. Thus, a diamond weighing 1.20 carats weighs 1 carat and 20 points.

How to know the weight in carats of a diamond

There are several ways to determine the weight of a diamond in carats. The first method is to weigh the diamond and divide its weight in grams by 0.2. For example, if you want to obtain the weight in carats of a diamond weighing 0.4 grams, you must divide 0.4 by 0.2, and you will get the weight in carats: 2 carats. This method for obtaining the weight of a diamond is only reliable if you use a high-precision scale. The scale must be able to display the weight to the hundredth or even thousandth of a gram, which will allow you to estimate the weight of the diamond as accurately as possible. Since carat weight is one of the elements used to estimate the price of a diamond, it is very important to estimate it as accurately as possible. To weigh a diamond with a high-precision scale, make sure the scale is at zero before weighing the diamond, and perform the weighing in a space free from drafts, vibrations, or other external disturbances to avoid influencing the displayed weight. Clean the diamond well to remove any dust that could impact the diamond's weight. Round the obtained weight up to the nearest hundredth. For example, a diamond of 0.999 carats will be rounded to 1.00 carat. A diamond of 0.997 carats will be rounded to 0.99 carats. Another method is to calculate the weight of the diamond based on its dimensions. Certainly, dimensions are different from carat weight. However, one can predict the dimensions of a diamond by knowing its weight, and the reverse is also true. However, this is not a matter of cross-multiplication: this method is therefore rarely used. But more and more diamantaires offer an online tool to easily calculate the carat weight of a diamond whose dimensions are known.

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Sell your jewelry At Diamantaire Paris, we understand the importance of every detail in evaluating a diamond. Our page dedicated to how to obtain the weight of a diamond offers valuable information for those looking to understand the value and quality of their precious stones. Our expertise is not limited to evaluation but also extends to the sale and purchase of high-quality jewelry. If you own historical pieces and wish to appraise, sell, or evaluate a Napoleon III jewelry item, our team of experts is at your disposal to provide you with an accurate and professional evaluation. We also understand the importance of wedding rings as symbols of love and devotion. If you are looking to sell a diamond wedding ring, we assure you a respectful and professional approach, ensuring your precious piece receives the attention it deserves. For those who own 1980s diamonds and are looking to sell them, our page sell 1980s diamonds offers advice and information for a successful sale. Our expertise is not limited to modern diamonds. We also offer evaluation services for diamonds certified by reputable laboratories. Whether you are looking to estimate an EGL diamond or to sell, estimate, or evaluate a diamond from the French Gemological Laboratory, our team has the expertise to guide you through the process. At Diamantaire Paris, every piece of jewelry is treated with the utmost care and respect. Our commitment to excellence is reflected in our wide range of services, including the estimation, sale, or evaluation of Chopard diamonds and the estimation or sale of Art Deco jewelry. Our expertise and passion for jewelry make us the ideal choice for all your diamond and precious jewelry needs. How can you determine the weight of a diamond without a certificate? To estimate the weight of a diamond without a certificate, you can weigh it and divide its weight in grams by 0.2. For example, a diamond weighing 0.4 grams equals 2 carats. It is recommended to use a high-precision scale for an accurate estimate. What is a carat and how is it used to measure diamonds? The carat is a unit of mass used to measure the weight of diamonds and other precious stones. One carat equals 0.2 grams (or 200 milligrams). It is different from the carat used for gold alloys. Can you estimate the weight of a diamond from its dimensions? Although the dimensions of a diamond are different from its carat weight, it is possible to predict the dimensions of a diamond by knowing its weight and vice versa. However, this method is not commonly used and requires specific tools. What is the importance of rounding in estimating the weight of a diamond? When weighing a diamond, it is important to round the weight up to the nearest hundredth for increased accuracy. For example, a diamond of 0.999 carats will be rounded to 1.00 carat. How can Diamantaire Paris OG help me with the estimation of my diamond? Diamantaire Paris OG offers free and confidential expertise for diamond estimation. You can contact them at 01 48 87 23 37, send a pre-assessment by email to [email protected], or go directly to their boutique at 43 rue Beaubourg, 75003 Paris.