Video by Daniel Fortune
In the 1953 film Gentlemen Prefer Blondes, Marilyn Monroe famously chimed that “diamonds are a girl’s best friend.” The chorus punctuates otherwise foreboding lyrics warning of fading looks, plummeting stocks, short-lived affairs, and the general uncertainty of life as compared to the steadfast value of jewelry. Lorelei Lee herself could appreciate that while a kiss may be grand, knowledge is, in fact, a girl’s best friend. In addition to working with vendors you trust, there are a few important factors and authentications that can help you determine a stone’s value. When in doubt, use context clues: jewelry should feel good to wear and look beautiful, well-proportioned, and well-constructed from all angles. Here, we share some expert insight into valuation.
The four Cs of diamonds (carat weight, cut, color, and clarity) are well-known, but who decides the subtle difference between “very slightly included” and “very, very slightly included”? Prior to the 1940s, trade terms for diamond quality were often nuanced lingo such as “watery,” used to describe a near colorless diamond, or “Cape color,” in reference to the largely pale-yellow diamonds from South Africa’s Cape of Good Hope region. When Robert M. Shipley founded the Gemological Institute of America (GIA) in 1931, he recognized the need for a system that could be utilized internationally to uphold trade integrity and buyer confidence. His son, Robert Shipley Jr., and successor, Richard T. Liddicoat, later expounded on his four Cs with a full color and clarity scale, along with objective methods and instruments for grading diamonds. Today, the GIA is the international authority on diamond grading. While not always available, it is good practice to ask if a diamond has a GIA report as it can eliminate a lot of the guesswork.
Colored stones (the most precious traditionally being rubies, sapphires, and emeralds) are valued for vibrancy and distinctiveness of color. However, even seemingly specific adjectives—such as the “velvety” or “sleepy” blue of rare Kashmir sapphires or “pigeon’s blood red” of prized Burma rubies—are often used to describe a subjective color. Additionally, gemstones have long been modified with a variety of treatment processes to improve color and clarity. In America, institutions like the American Gemological Laboratory (AGL) produce certifications detailing not just present treatment processes, or the preferable lack thereof, but the region from which a stone was mined. For comparison’s sake, the price per carat of a sapphire determined to have been mined in Ceylon (Sri Lanka) can be a fraction of one mined in Kashmir; situated high in the Himalayas, this small stretch of the Zanskar range was completely depleted by 1887, only five years after it was discovered. Any colored stone with specific regional attribution should come with the paperwork to back it up, like those certifications from the AGL or other international entities of equal report.