![]() ![]() The diamonds accenting the ring have a total weight of 3.37 carats. The gem is a very dark blue almost black color and weighs 70.79 carats. A real sapphire stone is very rare and valuable as a result, most of the sapphires on the market are actually fake look-alike stones. This large star sapphire from Sri Lanka exhibits a rare 12-rayed star, probably caused by two sets of mineral inclusions oriented at 30° from each other. When a stone is cut with a domed top and flat bottom, called a cabochon, the reflected light is focused into bright bands that form the "star." Needlelike crystals of the mineral rutile inside the sapphire crystal that are aligned in three directions, intersecting at120°, form a 6-rayed star. Asterism is caused by light reflecting off of parallel bundles of tiny hollow tubes or fibrous crystals of another mineral inside the gemstone. It is an interesting member of the gem kingdom because it displays an optical phenomenon called asterism. Star sapphire is considered a phenomenal stone. Morgan donated the Star of India along with the rest of the collection to the American Museum of Natural History. A British Army officer brought it to London, where it was cut by Albert Ramsay around 1905. ![]() This platinum ring has a round cabochon star sapphire as the centerpiece, accented with round brilliant cut diamonds set in "leaf-like" prongs, and baguette cut diamonds fanned on the sides of the shank. The Star of India is a huge blue star sapphire weighing 563.35 carats. ![]()
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