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Dr. John W. Valley retires from GIA board of governors
He is also known for his pioneering studies of zircon, the oldest gem, showing that habitable conditions and oceans existed on Earth far earlier than previously thought
![](https://www.jewelleryfocus.co.uk/wp-content/uploads/2023/11/w4yp1ojR-GIA-1200x900-1-e1700670987853-780x470.jpg)
Dr. John W.
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