Many gemstones are enhanced or treated to augment their beauty, strength or clarity. In certain stones, the treatments are commonplace. Champion Gems believes that our customers should be well informed about the stones they are purchasing.
While rubies are universally accepted as red corundum, there are differing opinions on what constitutes a ruby versus a pink sapphire. Rubies receive their red color from high levels of the trace element chromium, just as a pink sapphire has traces of chromium. It is the saturation that defines the category in which the corundum falls. Color is the most important to consider when evaluating a ruby, with transparency being the secondary criteria. In the case of rubies, the ideal color is a vivid, medium-dark red to slightly purplish red with a medium to medium-dark tone and either strong or vivid saturation. Like sapphires, rubies are not subject to the same clarity expectations as diamonds. Natural rubies and sapphires are far more rare, and are not graded at 10x magnification. Rather, they are graded and viewed on eye level; a high clarity ruby would be considered “eye clean.”
Blue sapphire is considered a primary color gemstone; the purer the primary hue, the more valuable the gemstone. Blue sapphires are colored by trace amounts of titanium and iron. By increasing the level of titanium and iron, the color saturation is also increased. The most common secondary hues found in blue sapphires are purple, violet and green. Purple and violet can contribute to the overall beauty of the color, while green is considered the bane of a blue sapphire. Blue sapphires with some internal inclusions are still highly valued, as long as the inclusions do not reduce brilliance, obscure color, or otherwise detract from the gemstone’s beauty. Sapphires are dichroic gemstones, meaning their color varies depending on the angle from which they are viewed. Viewed in one direction, most blue sapphires appear blue to violet-blue. From another direction, they will appear slightly greenish blue. Silk inclusions are also acceptable in blue sapphires, as long as they are not so dense as to compromise color or brilliance. In fact, silk inclusions can increase the value of a sapphire. The heat treatments used to alter color and clarity in blue sapphires break down rutile silk, so the presence of intact silk indicates that a sapphire is unheated. Heat treatment is widely used in the international sapphire market, and it is estimated that well over 90 percent of all blue sapphires in the market today has been subject to heat treatment.
Emeralds are among the most precious of natural gemstones, alongside rubies, sapphires and diamonds. Emerald is a type of the mineral beryl. Its green color is a result of small amounts of chromium and sometimes vanadium within the gemstone. Depending on the amount of these elements, the emerald can appear light green to a very deep, dark green. Emeralds are undeniably the most stunning and popular of the green color gemstones. For centuries, they have been among the most sought after and valuable gemstones symbolizing rebirth and love. Color is the most important factor when pricing emeralds and is broken down into three components: hue, saturation and tone. The most desirable emerald colors are bluish green to green with vivid saturation and medium to a medium dark tone. Emeralds tend to have numerous inclusions and surface breaking fissures. Unlike a diamond, where the loupe standard, i.e. 10X magnification, is used to grade clarity, emerald is graded by eye. Thus, if an emerald has no visible inclusions to the eye (assuming normal visual acuity) it is considered flawless. Stones that lack surface breaking fissures are extremely rare and, therefore, almost all emeralds are treated, “oiled” to enhance the apparent clarity.
Green tourmaline is a type of green crystal and is part of the tourmaline family, which also features colors such as red, yellow, blue, colorless and even black. Green tourmaline is considered the most common tourmaline gemstone, and is the classic color of the gem. While some of these gemstones feature a darker bottle green color, others can range from a very light green to a yellowish green or olive color. Certain green tourmaline stones feature a blue-green or darker green color.
In certain jewelry settings, the green tourmaline gemstone can often appear similar to the green emerald stone. The stone features a very high clarity rating as a type 1, and also has a trigonal crystal structure. It is rated a 7.5 for hardness on the Mohs scale, which means the stone is resistant to scratches, as well as other abrasions. Green tourmaline is considered lustrous and very refractive, and can be located in mines in Brazil, Pakistan, Madagascar, Afghanistan, Nigeria, as well as across the United States.