What Makes a Rock a Gemstone?

What is a gemstone? There exists in nature over three thousand crystals, minerals and biogenic materials, yet only a very small percentage of have the characteristics necessary to be classified as a gemstone. In order for a material to be considered a true gem, it must possess beauty, (color, luster, perfection of cutting and polishing, etc.) durability, rarity, and portability.

BeautyUnless a gem material is beautiful, it cannot be considered a gemstone. Beauty may be the sleepy blue fire of a beautifully cut sapphire, the kaleidoscopic "play of color" of the opal, or the mesmerizing green of the emerald.

DurabilityAnother essential quality of a gemstone is durability. This does not mean a gem must be indestructible; no such material exists in nature. However, a gem must wear well enough to retain its beauty for a reasonable length of time.

HardnessHardness may be defined as a material's resistance to scratching. The diamond is the hardest gemstone and the hardest substance known in nature. Nothing can scratch a diamond except another diamond. However, diamonds and many other "hard" gemstones can chip.

ToughnessToughness may be defined as the ability of a gemstone to resist chipping. Jade is the toughest gem in nature. Although jade may be cut and fashioned into figures, statues and even axe heads with ease, its resistance to chipping is extremely high.

Rarity The third factor contributing to the value of a gemstone is rarity. Generally the rarer a material, thehigher its value. However, some materials are quite common in nature but are sufficiently beautiful to be in demand as a gem. One such gemstone is amethyst: in its finest quality, it is very beautiful, yet its price rarely exceeds $200 per carat. Conversely, a fine quality ruby is very rare and may easily exceed $10,000 per carat.

Portability A sometimes overlooked factor contributing to the importance of gems is portability. This applies to any fine gemstone because it represents a high concentration of value in a small object, permitting the owner to transport great wealth on his person. This gives gemstones a "universal security value," greater than any other known commodity. Over the centuries, this factor has influenced royalty and wealthy families to invest a percentage of their funds in fine gemstones. When all else fails and governments collapse, gemstones could realize a quick and healthy return, for its owner, paving the escape for the unlucky refugee.

Find Which Gemstone Represents Which Birth Month

Use these convenient reference pages to learn about gemstones.