ҮНЭТ ЭРДЭНИЙН ЧУЛУУ | Natural history museum of Mongolia
This gemstone is made of alumina (Al 2 O 3: Cr) but becomes red, reddish-pink, or violet under the influence of chromium. It is one of the hardest gemstones with a hardness of 9 in the Mohs scale, and originated in syenite, pegmatite, and high-grade metamorphic rocks, and occurs in placer deposits.
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