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Ruby Cabochons
Ruby has been the world's most valued gemstone for thousands of years. In fact, even today, flawless top
quality rubies are more valuable and rare than top quality colorless diamonds.Ruby is the gem quality form of the mineral
corundum, and one of the most durable minerals which exists, a crystalline form of aluminum oxide. Corundum has a hardness
of 9 on the Mohs scale and is also extremely tough. In its common form, corundum is even used as an abrasive. Colors of Corundum
other than red are known as Sapphire. The element Chromium is responsible for the red color of this gem, but too much Chromium
can actually turn corundum emerald green in color. Heat treatment is very common in ruby gemstones (as is true for all forms
of corundum) and is used to dissolve "silk" inclusions, which results in a more transparent, more intensely colored stone.
The heat treatment is considered permanent and does not usually detract from the value of the stone.
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Incredible oval cabochon with great fire. This is a pretty large cabochon for this material. Approx. size:
9x 12.5 Weight: 5.35 cts.
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