Diamonds are measured by weight in "carats". Note that the measure of purity for gold is "karat" with a "k" and has nothing to do with diamonds.
In the chart above, the relative size of diamonds ranging in weight from ½ to 8 carats are shown.
Contrary to the widely held belief that diamonds form from coal under pressure, coal seams (deposits) never reach the depth inside the Earth's mantle to be subjected to pressures great enough to do the job. Instead, diamonds are formed from carbon in an igneous rock called kimberlite - which may be composed of carbon-12, the isotope of carbon that is characteristic of living things.
Diamonds normally form into octahedral (8 sided) crystals, although numerous variations on the cubic form are found in nature. In any case, the exact circumstances that produce very large diamonds are quite rare.
Because the larger a diamond is the more rare it is, the value of diamonds increases rapidly with weight. A 6 carat diamond will weigh twice as much as a 3 carat diamond, but the cost can be much more than double for stones of similar quality.
How Many Carats Are Enough?
When choosing diamonds, size need not be your only consideration. All of the factors that determine the value of a diamond should be taken into account. Ultimately, the purpose of your diamond will determine many of the characteristics of the satisfactory stone.
Contact The Diamond Broker and we'll guide you through the process of selecting the diamond that is right for you.