CHARACTERISTICS OF GEMSTONES

To paraphrase Holly Golightly from Breakfast at Tiffany’s, when one gets the blues, the only way to feel better is to go to Tiffany’s because nothing bad can happen there. It is an exciting experience entering a jewelry store! The lights and glass cases of sparkling jewelry can captivate because, simply, it is a thrill to purchase and wear jewelry. When purchasing gemstone jewelry, it is imperative that the 4C’s – Color, Cut, Clarity and Carat, are considered. Other qualities that should also be contemplated are Origin, Rarity and Durability.

Color is the most valuable characteristic of a gemstone. The composition and structure of the minerals in the rocks that eventually become gemstones is what gives them color. The array of colors make gemstones attractive and beautiful. The question regarding color is whether or not the color is natural or applied. There are four color treatments that can change the appearance of a gem. They are heat, irradiation, dyeing and straining. Heat is the oldest and most common of color treatments. It improves the color distribution and reduces any visible flaws. Irradiation enhances a gemstone’s color through low or high electromagnetic waves or energy particles. An example of irradiation is a color change from yellow to orange. Unfortunately, the change may only last for a few days. Dyeing and straining usually modifies the color of a gemstone only on the surface.

The cut of a gem influences the overall beauty of the stone. When a gemstone is cut, inclusions and blemishes are caused and can increase the value of the stone. There are many different types of cuts; such as, brilliant, step or trap, mixed, cabochon and fancy. Gemstones are also categorized by types. Type 1 gemstones are mostly free of inclusions. An example of a Type 1 gem is the blue topaz and the amethyst. Type 2 gemstones possess inclusions and include sapphires and rubies. The most inclusions are found in Type 3 gemstones, such as, the emerald.

The physical properties of a mineral are hardness, gravity and breakage. During mining of the minerals, breaking can happen by cleaving or fracture. Cleaving occurs along the planes of the weak composition or structure of the mineral. Fracturing breaks on the surface of the mineral. Since clarity determines the level of flawlessness by grading the internal and external characteristics of the gemstone, cleaving and fracturing affect the clarity. Internal flaws of the gemstone originate from within and may extend to the surface. Feathers, crystals, cracks and fissures are examples of internal flaws. External flaws are blemishes such as scratches and nicks. Great clarity equals great transparency which determines how well the light passes through the gemstone. The clarity of the stone can affect the price more than the cut.

A gemstone is measured by weight in carats. Just because a gem is huge and looks stunning when worn or displayed, does not always mean that it is the best quality stone. Usually though, a high number of carats translates into a bigger price tag.

The remaining factors not included in the 4C’s can also determine a gemstone’s worth. The origin of the mineral or where it is discovered and eventually mined can add to the stone’s value. If the location is difficult to reach, or the weather is extreme, that particular gemstone would be an asset to any jewelry collection. When the supply is exhausted and mining ceases, the scarcity or rarity of the gemstone increases its value. Finally, a durable gemstone is a smart purchase since it can withstand scratches and damage.

Examining all of the qualities listed above can assist in the addition of gemstones to a collection that can be passed on generation after generation.