Diamonds — The Four C's
Cut
Here's where the rubber meets the road in terms of beauty and value in diamonds. By Cut, we are referring to the proportions, angles and finish of a gem. This, more than any other quality, determines the fire and brilliance of a diamond, or any other faceted gemstone for that matter. Unfortunately, there is quite a lot of misinformation and myth surrounding Cut. It is a very complicated subject and we can only give you a small amount of information here. However, experience will tell you, as in tasting fine wines, just what you appreciate best in the look of a finished diamond. The more you look, the more your eye will become educated.
Having stated that, here then are the basics in the art and science of diamond cutting. From records, it has been determined that diamonds were first polished about 700 years ago, and that actual cutting, grinding and shaping was not accomplished until about 500 years ago. The art of diamond cutting was passed on from cutter to cutter for generations with trial and error being the mode by which improvements were made in bringing out the natural properties of diamond. Not until 1919 however, was optical science and mathematics applied to the process.
Since then, the cutter has walked a fine line between optical science and profitability. Here one must understand that the cutter's job is to maximize the value of a rough crystal through cutting and polishing. Generally, this job description produces medium to low quality in beauty, brilliance and value. Occasionally it produces fine to well, or "Ideal" cut gems that capture all the fire and romance that diamonds are capable of displaying.
The physics of cutting are actually the easy part. Extracting value is where the cutter's art truly lies. Believe it or not, often there is far more profit in cutting a stone too deep or too shallow than in adhering to optical standards. As with Color and Clarity, you can see that a well cut, or "well made" diamond is also quite rare. It is worth the hunt however, as value is always retained in beauty.
Much is made of the so called "Ideal Cut " diamond. Regardless of sales pitches, there is no exact standard of cut that is ideal. There is only a range of angles and proportions that, when achieved, will return the maximum brilliance and fire to the eye. As with the complexities of flavors in fine wines, the rarer gems will exhibit a complexity that produces the greatest brilliance from the greatest number of angles in the greatest number of lighting situations. This diagram shows the common ranges of angles and proportions for a round brilliant cut diamond:
Having stated that, here then are the basics in the art and science of diamond cutting. From records, it has been determined that diamonds were first polished about 700 years ago, and that actual cutting, grinding and shaping was not accomplished until about 500 years ago. The art of diamond cutting was passed on from cutter to cutter for generations with trial and error being the mode by which improvements were made in bringing out the natural properties of diamond. Not until 1919 however, was optical science and mathematics applied to the process.
Since then, the cutter has walked a fine line between optical science and profitability. Here one must understand that the cutter's job is to maximize the value of a rough crystal through cutting and polishing. Generally, this job description produces medium to low quality in beauty, brilliance and value. Occasionally it produces fine to well, or "Ideal" cut gems that capture all the fire and romance that diamonds are capable of displaying.
The physics of cutting are actually the easy part. Extracting value is where the cutter's art truly lies. Believe it or not, often there is far more profit in cutting a stone too deep or too shallow than in adhering to optical standards. As with Color and Clarity, you can see that a well cut, or "well made" diamond is also quite rare. It is worth the hunt however, as value is always retained in beauty.
Much is made of the so called "Ideal Cut " diamond. Regardless of sales pitches, there is no exact standard of cut that is ideal. There is only a range of angles and proportions that, when achieved, will return the maximum brilliance and fire to the eye. As with the complexities of flavors in fine wines, the rarer gems will exhibit a complexity that produces the greatest brilliance from the greatest number of angles in the greatest number of lighting situations. This diagram shows the common ranges of angles and proportions for a round brilliant cut diamond:
As you can see, there is a substantial range within all of the criteria. This gives the cutter incredible flexibility in say, lowering the table to avoid an inclusion – thereby improving Clarity; or deepening the pavilion to bring the weight just over 1.00ct. – improving the price per carat bracket.
Here are some illustrations of what happens to the path of light as it travels into, through and back out of a cut diamond:
Here are some illustrations of what happens to the path of light as it travels into, through and back out of a cut diamond:
Here you can see that when a diamond is cut with too deep of a pavilion, light coming into the stone from the top "leaks" out the bottom and/or crown instead of being reflected and returned to the eye. This generally produces a stone that has the appearance of a dark center.
If the diamond is cut with either too shallow of a pavilion or crown, light passes through the stone and out of the bottom, or bounces and passes out of the crown. Again, the light is not returned to the eye. These stones often look watery and lifeless and sometimes dark, with a minimum of brilliance.
When a diamond is cut accurately, light passes into the stone through the top surface (table and crown), diffracts and reflects off the interior surfaces of the pavilion, and bounces back out of the table and crown facets, returning the natural dispersion and brilliancy that is inherent in a well cut diamond. A truly well cut diamond will still achieve maximum brilliancy even when viewed from an oblique angle, not just from the top. Here are a few tips that a diamond may be cut poorly:
Of course, the stone must be clean and free of oils, hand creams, etc. Anything adhering to the outer surface of the stone will interfere with the light. It is of utmost importance that you keep your jewelry and gems clean after your purchase if you want them look their best.
With an investment in a well cut diamond, you will have a stone that is special, gets noticed and is a pleasure to own and wear.
- it seems dull – especially outside of the jewelry store's "hot" lights
- it looks glassy or watery
- it appears foggy
- some areas sparkle more than others
- it appears dark in the center
- the sparkles seen through the table seem to be large "checkerboard-like" spots rather than many small pinpoints of complex light
- the shape does not appear symmetrical either from the top or the side view
Of course, the stone must be clean and free of oils, hand creams, etc. Anything adhering to the outer surface of the stone will interfere with the light. It is of utmost importance that you keep your jewelry and gems clean after your purchase if you want them look their best.
With an investment in a well cut diamond, you will have a stone that is special, gets noticed and is a pleasure to own and wear.
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