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The value of gems is often determined by a particular gem's possession of certain qualities such as clarity, transparency, and color. Other factors include fashion, rarity, and durability. Each gem has a different meaning and is meant to be worn for certain occasions.

Diamonds are the hardest and most glitsy and brilliant of all the gemstones. They are by far the most desired stones known to man. The diamond industry maintains that there are four important factors when determining a diamond's value: color, clarity, cut, and carat. A perfect diamond is colorless, has no internal marks or blemishes, and is cut by a skilled laborer in such a way as to reveal the stone's amazing color and brilliance.

No two pearls are ever the same. Pearls are worn usually in necklaces, and are judged mainly by their absence of marks and blemishes, size, color, and luster. It is difficult to create a valuable pearl necklace. There are so many variables with pearls that it takes an incredible eye to sort pearls into such a group to compile a necklace of pearls that are very similar in size, color, and luster. Natural pearls are found mainly in oysters and clams in the Pacific Ocean, the South Sea Islands and the Persian Gulf.

Emeralds are incredible to look at. They are cut from the green variety of beryl, a mineral. Emeralds are judged on their transparency and "velvety-ness." While emeralds are hard stones, they can, in fact, break. So you must be careful when wearing or handling an emerald.

Rubies are cut from the mineral corundum, and are transparent or translucent red. The highest quality rubies have limited hints of other tints or colors.

Sapphires also are cut from corundum. They can take on a variety of colors, however, ranging from blue to yellow to green. There are sapphires which contain as many as six colors. These are known as "star sapphires."