People mark special events with sentimental gifts of jewelry. While weddings reign as the biggest diamond event, there are many small celebrations that are honored with beautiful diamonds, too, such as new jobs, anniversaries, graduations and births.

So how do people learn about diamonds so they can buy, own and enjoy them with confidence? The nonprofit Gemological Institute of America (GIA), the world’s foremost authority in gems and jewelry and the creator of the famous “Four Cs” of diamonds offers these tips:

Research. GIA’s Web site on www.gia.edu offers in-depth information on diamonds, pearls and other gemstones. GIA even built a special www.gia4cs.gia.edu Web site on the Four Cs. Knowing the Four Cs helps you speak the language of diamonds and communicate with jewelers.

Learn the “Four Cs.” All diamonds are rare and no two diamonds are alike. A diamond’s quality and rarity is determined by its unique combination of characteristics of Color, Cut, Clarity and Carat Weight. The International Diamond Grading System, used around the world since its invention by GIA in the 1950s, is based on the Four Cs.

• Carat: Diamonds are weighed in metric carats. Two carats weight about the same as a small paper clip. A carat is divided into 100 “points”, so a diamond of 50 points weighs 0.50 carats.

• Clarity: Nearly all diamonds contain unique clarity characteristics. Flawless diamonds are exceptional and costly. Most inclusions are invisible unless magnified.

• Color: Colorless diamonds are extremely uncommon. Most diamonds have a slight yellow or brown tint. GIA uses letters to represent colors, beginning with D (colorless) and ending at Z (light yellow or brown). “Fancy colored diamonds” come in every color imaginable, are also very unusual and have their own GIA color grading system.

• Cut: While diamonds come in different shapes, such as round, pear or marquise, the term “cut” refers to proportion. The well-cut, balanced diamond has unbridled brilliance, sparkle and fire.

Get an independent diamond grading report. A diamond grading report tells you the exact gemological quality of your diamond. Is it a natural diamond? Is it a synthetic diamond? Has it been treated and how? What are its quality ratings according to the Four Cs?

Have your diamond appraised and insured. A diamond grading report describes the precise gemological quality of your diamond while an appraiser puts a monetary value to the stone. You can laser inscribe a personal message or the diamond’s unique GIA Grading Report number on the diamond’s girdle.

Source: Gemological Institute of America (GIA) October 2008