3/2/2023 0 Comments Topaz clarity![]() ![]() It’s possible this was a white topaz turned brown by irradiation. This pear-shaped topaz (18.88 cts, Russia) has an unusual, coffee-brown color. The process so nearly duplicates what happens in the Earth, a treated stone cannot be distinguished from a natural. Then, the brown stone is heated to achieve a stable, blue color. First, the rough is irradiated, turning it brown. In the 1960s, a two-step method was discovered to turn colorless topaz blue. While topaz has been synthesized in labs, it's not usually commercially available. The specific gravity (SG) and optics of topaz vary by stone color. Custom-cut imperial topaz, 9.60 cts, Brazil. Topaz has different physical and optical properties than citrine, most notably greater hardness and brilliance. However, citrine is a quartz, a distinct gem species. With the advent of modern gemology, many of these stones were re-classified as different species.īecause of topaz's long association with the color yellow, citrines are sometimes misidentified as topazes. Traditionally, all yellow, brown, and orange transparent gems were called topaz. Photo courtesy of and Jasper52.įor more information on topaz quality factors, consult our buying guide and engagement ring guide. A safe and very common heat-and-radiation treatment gives them striking, darker colors. However, almost all such gems began as colorless or pale blue topazes. Used with permission.īlue has become the most popular color for topazes on the market today. Oval-cut precious topaz, 11.30 cts, Brazil. The term “precious topaz” refers to stones with a rich yellow to a medium, peachy orange color. Colorless topazes are common and are low-value gems in any size. Intense, reddish orange topaz is sometimes called “imperial topaz.” Yellow, orange, and brown stones are somewhat common. The highest values go to the rare pink and red stones, then orange and yellow. Although clarity and size have a significant effect on the value of topaz, color has the greatest impact on pricing. ![]()
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