Zircon
“Earth's oldest surviving crystal”
Zircon is a zirconium silicate mineral prized both as a gemstone and as the most important mineral for dating the age of rocks. Tiny zircon crystals are nearly indestructible — they can survive weathering, erosion, metamorphism, and even partial melting of rock, preserving records of events billions of years old.
zirconium silicate (ZrSiO₄)
Jack Hills (Western Australia), Sri Lanka, Cambodia, Tanzania, Ural Mountains (Russia), North Carolina (USA)
7.5
The oldest known material on Earth is a 4.375-billion-year-old zircon crystal from Australia's Jack Hills — it formed just 165 million years after the planet itself.
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Why is zircon the most reliable mineral for dating events in Earth's earliest history?
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