Topaz is an important group of gemstones known for excellent value. Though most topaz gemstones are faceted to bring out color, stunning cabochons can be found in nearly every shape and assorted colors. Blue topaz cabochons are in heavy demand for fashion jewelry, typically lighter blues, such as 'sky' or 'Swiss' Blue. London-blue color is a bit dark for cabbing rough, but can also be sourced quite easily. Colorless cabochons are rarer to find in topaz, mostly since there is not much demand. Large gemstone cabochons are easily sourced when it comes to topaz, though perhaps not as abundant as some varieties of quartz. Most topaz nowadays is mined from Brazil, where it is also often treated to create the lovely different shades of blue to greenish-blue hues.
While Brazil has much experience when it comes to mining and processing of gems, they do lack in the number of skilled gem cutters, which is why most Brazilian gems are exported to 'gem hubs' such as India, China, Hong Kong and Thailand (Chanthaburi) where they are to be cut, polished and traded.
Technically, cabochons are not actually 'cut', but rather shaped and then polished. Before the times of faceting, all gemstones were worked into cabochons or into gem carvings. Topaz cabochons can be formed into any shape, though oval cabs are most common. Topaz combines affordability with superior hardness (8 on the Mohs scale). Though due to perfect cleavage, it may not be as durable as softer gems like tourmaline when it comes to knocks and blows.
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Many beautiful gems on the site. Love that you are actually shipped the gem that is shown in the photos. Also cool that they give a write up of each gem detailing hardness, characteristics, and best uses for mounting. Great site! Looking forward to seeing these gems in person.