Shopping for Diamonds and Pearls
How to Get Good Value When You Buying Pearls and Precious Stones
The second of three articles on shopping for fine jewelry, this article covers the origin of pearls and the "Four Cs" of diamonds: Color, Carat, Clarity and Cut.
In a previous piece, we explored tips for buying gold, silver and platinum jewelry. We continue with our treasure hunt, this time looking at pearls and diamonds.
Pearls
Always ask whether the pearls are natural (created by the oyster on its own with no human intervention, and extremely rare); cultured (created by the oyster with human intervention, most common); or imitation (man-made with various materials).
A cultured pearl’s value is based on size, which is measured in millimeters, and the quality of its “nacre,” the exterior coating that gives pearls their luster.
Color is also important in determining value. The most common color is white, but pearls can also be ivory-colored, peach-colored, gray or black.
The most expensive and highly-prized pearls are Tahitian Pearls, huge black pearls with a high luster that are cultured in the islands of the South Pacific.
While many colors of pearls occur in nature, some are dyed. A jeweler should tell you if a pearl is naturally-colored or dyed, as this affects value.
Diamonds
A book could be written on determining diamond quality, and many have. The most important thing to remember is the “4 Cs” – color, cut, clarity and carat.
Color
Diamonds have established grading systems for color and clarity. Since diamonds can occur in several different colors, each color has its own grading scale. White diamonds are the most common, and their color is graded from colorless at the very top of the scale, to faint yellow or brown in the middle, to light yellow or brown at the bottom. A colorless white diamond is most rare and therefore the most valuable.
“Fancy” color diamonds such as champagne (golden-brown), canary yellow, blue, green, purple, pink and red each have their own grading charts. The majority of fancy-colored diamonds, other than the champagne and yellow, are irradiated to achieve their color. Natural blue, green, purple, pink and red diamonds are so rare they can cost hundreds of thousands of dollars per carat.
Cut
The cut is the shape of the diamond, and how many facets it has. Cut is highly important, as it determines a diamond’s sparkle, flash, and radiance. Popular cuts include round, princess (or square) cut, baguette (elongated rectangle), and heart-shaped.
Clarity
Clarity is graded from top to bottom, with “flawless” being the highest grade. In a flawless diamond, a gemologist cannot see any surface or interior cracks, fissures, or spots (inclusions) at 10 power magnification.
An internally flawless diamond has no interior inclusions, but may have minor blemishes on the surface of the stone. There are many levels of clarity classification, down to stones with large inclusions that are visible to the naked eye.
Carat
Carat (with a “C” instead of the “K” used for metal purity) is the weight of a diamond, which determines its size. The type of cut will have a bearing on a diamond’s weight.
When purchasing a diamond, always ask for certification of the diamond’s characteristics from a gemological lab, certified appraiser, or a reputable gemological organization such as the Gemological Institute of America (GIA).
In part three, the basics of precious and semi-precious gemstones will be covered.
