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Engagement Ring
Diamond Carat Guide

Carat weight is a measure of a diamond's size. The word "carat" comes from the ancient method of weighing diamonds: by balancing them on a scale with carob seeds! Of course, technology has become much more sophisticated, and measurements more precise; yet the terminology is a reminder of the long history of these gems.

One carat weighs one-fifth of a gram, or 200 milligrams. When diamonds are smaller than one carat, their weight is expressed as a fraction of a carat, or in "points." One carat equals 100 points. Therefore, 3/4 carat (.75 carat) equals 75 points, 1/2 carat (.50 carat) equals 50 points, 1/4 carat (.25 carat) equals 25 points, etc. Points are an easier way to express more complicated fractions, such as .43 carat, or 43 points.

Diamond measurements will vary, but to give you a rough idea, a one carat round diamond will usually measure around 6.5 millimeters in diameter. A 1/2 carat diamond will measure around 5 millimeters in diameter, and a 1/4 carat around 4 millimeters. It is important to note that diamond dimensions can vary considerably (ie., a one carat diamond will not always measure 6.5 mm in diameter). If you are purchasing a diamond for a specific mounting, you will usually need to know what size diamond (in millimeters) will fit into the mounting.

Carat weight is the most significant factor in determining the price of a diamond. As you might expect, the larger the diamond, the higher the price. The increase in price with size, however, is a bit more complicated. A one carat diamond is not simply double the price of a half carat diamond. The price of a diamond rises exponentially, rather than linearly, with size. Mother Nature gives us many more smaller diamonds than larger ones; if a thousand rough diamonds are dug from a mine, only one or two may be large enough to yield a one carat finished stone. Since larger diamonds are much rarer, they are much more expensive.

Budget is not the only factor to consider when choosing your diamond's carat weight; the tastes and lifestyle of the wearer are also important. Everyone assumes that a woman wants the biggest diamond possible; however, this is not always true. Some women feel more comfortable wearing a smaller diamond, as it may be more suitable to their personality, or their workplace. Others who are very active, or use their hands a lot (like nurses), often prefer engagement rings with smaller diamonds for a very practical reason: smaller stones do not project outward from the ring as much, and are therefore less likely to catch on things during the day.

Selecting a carat weight involves striking a balance between size and quality. The largest stone available at a certain price (say $2000) will usually have the poorest color and clarity; for that same $2000, you can purchase a smaller stone of better color and clarity. It's a matter of deciding what characteristics are important to you, and then finding the best combination that fits your budget.

Our next article is about Clarity >>


Other Articles:
Diamond Clarity
Diamond Color
Diamond Cut
Antique Diamonds
Asscher Cut Diamonds
Jewelry Metals
Engagement Ring Styles
Celebrity Engagement Rings
History of Engagement Rings
Antique Engagement Rings Gallery
Proposal Guide
Proposing on a Grand Scale
Buying an Engagement Ring on a Budget
How to Clean and Care for Your Engagement Ring