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sapphire

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  • 25 June 2026The 100-Million-Year-Old Volcano That Filled a Lake with SapphireHow a 100-million-year-old volcanic eruption in eastern Queensland created the Anakie sapphire fields—not in molten rock but in a quiet lake where gems crystallised from cooling ash.
  • 11 May 2026The Sapphire Gravels: Gemstones of the New England GemfieldsBeneath New South Wales' New England region, 50-million-year-old volcanic gravels hold sapphires and zircons carried from deep within the continent's crust.
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