The 4 ‘C’s’ for Buying Diamonds


In the series Early Holiday Unwrapped, jewelry expert Carol Brodie spoke to Maggie Rodriguez about this season's jewelry trends and the four "c's" to remember when buying a diamond.

A Karat, A Carrot, A Carat ? How Do We Measure a Diamond?

Karat is the Gold measurement. It is used to measure the purity of gold.

Carrots, of course, are bunny food and diet snacks.

Diamonds are weighed by the carat (ct)  One carrot weighs 200 milligrams or 1/2 gram.  This has been the weigh scale since 1913. Before that, the carat differed from country to country.  An older stone could weigh heavier than the modern weight.

Carat weight is often referred to as points. One carat = 100 pts.

A stone with 25 points = 1/4 carat.

This is weight not size.

Diamonds are priced by the carat and quality of the stone.  A very fine diamond weighing  1 carat would be much higher priced than one of poorer quality.

Another term used by jewelers is  “spread”  This refers to the  “look”  of the diamond.  A lot is determined by the cut of the jewel.

The way it is cut and set into a casing can make the stone appear much larger than it really is.

The carat weight is always determined before it is put in a setting. However some jewelers may price by the “look” of the stone.

To avoid this always by from reputable dealers.

When buying a very valuable diamond, you should always receive a certificate of worth.  You should also have it appraised by a certified gemologist.  Beware of scammers – even on New York’s famous 47th street.  Research and be knowledgeable.  take the time to get it right – after all a diamond last a lifetime.

For examples of settings and spread click here.

An excellent book for anyone thinking of purchasing precious stones is

“Jewelry and Gems” The Buying Guide – by Antoinette Matlins

Our resources: “Jewelry and Gems”  as well as Wikipedia, also” The Encyclopedia  of Gemstones and Minerals ” by Martin Holden.