What you "C" is what you get. The diamond is a true marvel of nature. Magical. Mysterious. Universally treasured. And no two are exactly alike. Yet choosing a diamond you'll both love is not so mysterious - when you understand the characteristics that distinguish one gem from another. Any explanation of a diamond's beauty and value centers on three key quality factors: cut, color and clarity, and one unit of measure: carat weight. Collectively these are known as the four Cs. Learn what to look for. Decide your priorities. Then make the choice that's right for you.

The 4 C's of Diamonds

Cut

A diamond that is masterfully cut displays maximum brilliance and fire. Cut and proportion are extremely important because they have the greatest influence on the sparkle and value of a stone. A diamond that is well cut reflects light from one facet to another and disperses it back through the top of the stone.

Color

A diamond's body color can range from totally colorless to light yellow. The whiter or more colorless the stone, the more costly, because the absence of color is more rare. Also, the less color in the stone, the easier it is for light to pass through and be dispersed back into the spectrum of colors, like a rainbow.

Clarity

Nature is rarely perfect. So it is very rare to find a diamond that is completely pure or free of inclusions - minerals or crystals trapped within the stone at the time it was formed. Without ten-power magnification, you may never see these tiny inclusions. But they are the fingerprint that makes each diamond unique.

Carat Weight

The size of a diamond is defined by its weight, which is expressed in carats. One carat weighs one-fifth of a gram, and is divided into 100 points - like pennies to a dollar. The larger the diamond the more rare and costly it is. However, depending on their color, clarity and cut, two diamonds of the same carat weight can vary widely in their value.

Here is a sample of diamonds that are available right now on ebay:

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	230 Carat D SI1 Very Good Cut Round Natural Loose Diamond EGL Certified	$19,569.00	30m

	125 Carat I VS2 Excellent Cut Round Natural Loose Diamond GIA Certified	$9,170.00	30m

	301 Carat I VS1 Very Good Cut Round Natural Loose Diamond GIA Certified	$67,581.00	30m

	201 Carat K VS2 Excellent Cut Round Natural Loose Diamond GIA Certified	$17,762.00	30m

	403 Carat I SI1 Very Good Cut Pear Natural Loose Diamond EGL Certified	$23,039.00	30m

	101 Carat E SI2 Excellent Cut Cushion Natural Loose Diamond GIA Certified	$4,010.00	33m

	206 Carat H SI1 Excellent Cut Round Natural Loose Diamond GIA Certified	$25,707.00	33m

	071 Carat F VS1 Excellent Cut Round Natural Loose Diamond GIA Certified	$4,221.00	33m