As the weather cools and we begin stepping towards winter, we look for bright spots to keep our spirits up -- a clear blue sky on a crisp, cold day, or the blush of changing leaves on the trees in the coveted autumnal sunlight. The primary birthstone for November, Topaz, is just the stone to bring a bit of color and light to those colder days ahead.
Topaz is a highly prized gemstone, known throughout history for its gorgeous sparkle. Topaz most commonly forms in a golden-brown color palette, and can also be colorless, pink, or pale blue. Many gemstones get their color from trace amounts of elemental impurities in their chemical compositions (such small amounts that they are not even reflected in the mineral’s chemical formula). Other times, microscopic irregularities in the gem’s crystal structure cause the mineral to exhibit a certain color. Depending on the gem and what causes its color, different types of laboratory treatments can be used to intensify the color (and sometimes, clarity) of gemstones. This is a perfect opportunity to talk a bit about gemstone treatments and why they’re not always a bad thing!
London Blue Topaz is a perfect example of how a treatment can enhance the qualities of the stones that we love without causing any problems for its quality or lifespan in jewelry; colorless or pale blue Topaz undergoes gentle irradiation and heat treatment to bring out a range of blue colors, allowing us to attain the desirable deep blue color that so rarely occurs in nature. It does not affect the durability or longevity of the gemstone and, for Topaz, is considered a safe and enduring treatment.
Other gemstone treatments are not so innocent. Surface Coating, for instance, involves the application of a thin film of color to a gemstone with the intention of temporarily altering its appearance. Besides the fact that coating a gemstone with metal oxides or a film of color feels blatantly dishonest, this is not an effective (or very respectable) gemstone treatment because it doesn’t last. Dyeing is similarly undesirable as a gemstone treatment for the same reason. Other treatments including fracture-filling and stabilization, which are both used to change the clarity or stability of a gemstone, are common but not especially trustworthy, as these treatments are not enduring and can sometimes cause other problems (i.e. brittleness).
All gemstone treatments should be disclosed to the consumer, because the type of treatment can affect the value of a gemstone. When that information is not disclosed, sometimes the trade name of a gemstone will give away any treatment it has been subjected to: so-called “Mystic Topaz,” for example, is coated with a metallic lacquer that gives it an “Aurora Borealis” effect. Although it may technically be the gemstone Topaz, its trade name can alert a savvy buyer to the fact that it is not in its natural form. As described above, coating treatments like this one are not reliable, as they won’t last.
Although we at Silver + Salt prefer to use natural, untreated gemstones as much as possible, occasionally we source gemstones that are heat-treated; this is fairly routine in the trade, does not degrade the value of the gems, and can help us make certain colors available to our customers. We will never use gemstones that can’t stand the test of time, so you’ll never find fracture-filled, stabilized, dyed, or surface-coated gemstones in our work.
The beautiful color of London Blue Topaz that results from these select, trustworthy laboratory treatments allows us to enjoy these vibrant gemstones even more. Whether these blue tones evoke a clear, open sky or a deep and mystical lagoon, we hope that our newest collection celebrating Topaz as November’s birthstone brings a little color and sparkle to your winter days.