Fancy Favorites: A Love Affair With Rubies and Sapphires

Another, extremely rare, phenomenon is that of changing colors under different light sources. These very uncommon and highly valued stones change color from a blue-green in daylight (or fluorescent light) to purple in yellow light (incandescent light).

Both these stones are highly sought after by collectors and command premium prices.

Most sapphires are faceted in a variety of shapes. Oval and cushion shapes are the most common, but other shapes such as emerald, heart, princess and new innovative cutting styles, are not uncommon. These new styles were originally developed in the diamond cutting industry and adopted by sapphire polishers. Round brilliant cut sapphires have also become popular, appealing to creative designers and jewelers. When choosing a cut, look for pleasing overall proportions and quality finish. A good cutter may sometimes alter a cutting style to a slightly deeper pavilion to get a more intense color. This style is sometimes seen in sapphires from Sri Lanka in order to bring a lighter shade rough to a more vibrant color.

When buying sapphires, bear in mind that color, size and availability are the most important factors determining the stone’s beauty and value. However, natural color sapphires are not found in even color shades to meet demand. Sapphires today are therefore heat treated and diffused with chemical additives, or irradiated, to produce more intense, even or unusual shades color that can be sold at affordable prices to the consumer.

In order to achieve better clarity, sapphires are treated to attain increased transparency and brilliance. This treatment is performed by filling the highly visible fissures and cracks with a glassy material containing lead or borax. However, this treatment sometimes leaves behind telltale features such as “flashes of blue color“ in the fissures, due to small differences in physical properties of the lead glass and the sapphire. Recent development includes filling sapphires with a molten solution of sapphire, thus leading to a more even match of gemstone and filling material. This treatment can only be detected by an experienced gemologist.

In the jewelry trade, full disclosure of any treatments is mandatory, especially for treatments that are not permanent, and that require special care by the wearer. Some colors that result due to these heat treatments have been known to fade in sunlight. Other treatments such as fracture filling become unstable due to normal daily wear and contact with common household liquids like lime juice, vinegar and bleach. Such treatments must be disclosed to the buyer during the time of sale, in order to protect the consumer. If in doubt, send your sapphire to a reputable laboratory for grading, as lab reports commonly mention any treatments found during analysis. Most treatments on sapphires are accepted by the trade but they must be disclosed during any transaction.

Untreated color sapphires, especially pinks, are becoming popular but only a few jewelers have access to reliable sources, due to price uncertainties and a lack of consistent quality stones. Top quality untreated color sapphires with perfect color and clarity match may be difficult to find, but they do exist, at a price. To find them, you need patience and In-depth knowledge.

 Most transactions and sales for these premium sapphires take place only when accompanied with a certificate from a reputed lab so as to safeguard the buyer as well as the seller from possible synthetic and treated sapphires.

The origin of sapphires also plays a large role in determining demand and therefore also their price. Various locations around the world are highly desired for different colors.

This trend of preference has existed since ancient days and is the result of legend. Whatever the current situation may be, this preference continues to this day. For example, blue sapphires are highly valued when sourced from Kashmir, whereas yellow and padparadscha sapphires from Sri Lanka command premium prices.

That being said, an exceptionally fine color sapphire from Nepal will still have greater value that a poor and uneven color sapphire from Sri Lanka.

Synthetic sapphires exist in the market in large numbers as there are multiple methods to synthesize them. These synthetic stones are available in a large range of sizes and very fine colors. Most synthetic stones can be identified under proper magnification and observation of their inclusions. Clean stones may need further analytical tests. The most frequently encountered synthetic color sapphires are produced by the Verneuil (flame fusion) or hydrothermal process. Therefore most consumers and dealers need to be careful of such synthetics as intrinsically there is no value attached to these stone because there is no rarity and they can be mass produced.

In order for a customer to protect himself or herself against inadvertently purchasing synthetic stones, certification from an independent and well-equipped gemological laboratory is a must.

IGI has been at the forefront of gemstone identification and diamond certification since 1975. Every state-of-the-art IGI Laboratory around the world is equipped with the latest gemological equipment for gemstone identification and diamond testing. IGI also specializes in origin determination for gemstones. IGI’s highly trained and experienced gemologists ensure that the gemstone trade and end consumers can purchase colored stones with absolute confidence.