Carat is the unit of weight by which diamonds are measured. Carat is actually a measurement of weight and not size. One carat is divided into 100 points, for example 150 points would equal one and a half carats. One carat is equal to 200 milligrams.
Some people prefer larger caret diamonds above the other three c’s and some people prefer smaller diamonds with better clarity, cut and color. Although a higher carat weight may increase a diamond’s rarity and value, the cut, color, and clarity of a diamond also influence the price. Small diamonds can actually be more expensive than larger diamonds if the other three c’s rate highly.
Don’t make the mistake of buying the biggest diamond at the best possible price. You will likely end up with a diamond that is inferior in quality in cut, clarity and color that it will simply look cheap when your partner compares it to her best friend’s smaller diamond. There is nothing wrong with putting more importance on the size (carat weight) of a diamond but do consider the other three c’s to make sure you understand your tradeoffs.
Carat weight is the easiest of the four c’s to determine, but the diamond must be loose. Some jewelers approximate carat weight, for instance, when you want to buy a one carat diamond, which should to be 100 points, you may actually be getting less than that.
Again, this is where a diamond certificate will come in handy, as an un-bias documentation of a diamond’s vital data and all its characteristics and attributes that will affect its value, to take the guess work out of what you are interested in buying.
A diamond that has a balance of cut, color, clarity and carat is your best choice for quality and value.