Chrysoberyl is the third-hardest, frequently encountered natural gemstone, and it ranks at 8.5 on the Mohs scale of mineral hardness. Chrysoberyl is yellowish-green and transparent to translucent.
The three main varieties of chrysoberyl are: ordinary yellow-to-green chrysoberyl, cat's eye, and alexandrite, the most famous of all due to its color change. It's considered one of the rarest gemstones and the most expensive if it exhibits a 100% color change. The main source of chrysoberyl is Sri Lanka, Madagascar, Tanzania, the USA, Brazil, India, and many more

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