Emerald is a precious gemstone and a variety of the mineral beryl colored green by trace amounts of chromium and sometimes vanadium.
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Australia is a country and continent surrounded by the Indian and Pacific oceans. Its major cities ? Sydney, Brisbane, Melbourne, Perth, Adelaide ? are coastal. Its capital, Canberra, is inland. The country is known for its Sydney Opera House, the Great Barrier Reef, a vast interior desert wilderness called the Outback, and unique animal species like kangaroos and duck-billed platypuses.

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