A volcanic island in the southwestern Indian Ocean, Anjouan, has a strange geological mystery. Residents and geologists on the island keep finding an unusual rock. The island is made of basalt, which formed when tectonic plates shifted away and magma rose and cooled in an ocean basin. Quartzite, a sedimentary rock made from quartz sand …
Gazing Into a Diamond s Flaws Has Revealed Hidden Clues About How Our Planet Formed
15 MAY 2021
More than mere beautiful, coveted stones, diamonds hold another sort of wealth: fragments of Earth s deep history.
From flaws within the mineral s near-perfect lattice, scientists have just worked out how to extract long-hidden records of our planet s past.
We like the ones that no one else really wants, said geochemist Yaakov Weiss from Columbia University, referring to the diamonds full of impurities that don t look as clear and shiny as those desired for jewelry.
These fibrous, dirty-looking gems are where tiny vaults of information lie, stuffed with messages from Earth s inner depths. The carbon structure of a perfect diamond doesn t contain enough radioisotopes to help researchers date it, but the microinclusions found in its flaws can.
Diamond liquid impurities provide new insights into ancient Earth
Yaakov Weiss
Yaakov Weiss 2/3
The researchers analyzed the ratio of elements in liquid pockets trapped in diamonds, and identified three separate periods of diamond formation in Africa s ancient past
Yaakov Weiss
Yaakov Weiss
Geologists have studied tiny pockets of fluids trapped inside diamonds to get a better understanding of how old humanity’s favorite rocks might be. In doing so, they identified three distinct periods of diamond formation in Africa over the past few billion years, with intriguing implications for our planet’s history.
We’re sorry to break it to you, but as pretty as the diamond in your ring or necklace may be, it’s extremely boring from a geological perspective. That’s because the gem-quality diamonds so prized by the jewelry industry have to be as pure as possible, meaning they don’t have any “inclusions” of other elements trapped inside.
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IMAGE: A diamond encapsulating tiny bits of fluid from the deep earth, held here by fine tweezers, was part of a study delving into the age and origins of South African. view more
Credit: Yaakov Weiss
Diamonds are sometimes described as messengers from the deep earth; scientists study them closely for insights into the otherwise inaccessible depths from which they come. But the messages are often hard to read. Now, a team has come up with a way to solve two longstanding puzzles: the ages of individual fluid-bearing diamonds, and the chemistry of their parent material. The research has allowed them to sketch out geologic events going back more than a billion years a potential breakthrough not only in the study of diamonds, but of planetary evolution.