According to researchers from the Carnegie Institution's Department of Terrestrial Magnetism and the University of Cape Town, diamond flaws and inclusions are clues to continental formations on Earth. Specifically, diamond inclusions reveal vital information about past behavior of the Earth’s surface, such as that of continents breaking and drifting apart.

 

Unaltered impurities are preserved perfectly inside diamonds and can divulge chemical information about the past environment in which they were formed.

 

“We used the impurities, or inclusions, contained in diamonds, because they are perfect time capsules from great depth beneath the continents. They provide age and chemical information for a span of more than 3.5 billion years that includes the evolution of the atmosphere, the growth of the continental crust, and the beginning of plate tectonics,” said Steven Shirey, a geochemist at the Carnegie Institution for Science.

 

Ironically, the same flaws that reduce a diamond’s value in the consumer marketplace can reveal profound clues about how continents behaved millions of years ago. Mineral inclusions in diamonds are the oldest and most valuable samples of the Earth’s mantle, for instance.

 

Some of the diamonds researched had been lodged over 100 miles beneath the Earth’s surface for billions of years, at one point, and eventually expelled by volcanic eruptions. By discovering that traces of certain minerals found in the Earth’s mantle stopped appearing in diamond inclusions across the globe, researchers surmised that a major change occurred on earth about three billion years ago in which liquid rock beneath the earth’s surface mixed with the ocean floor, resulting in the breaking and drifting apart of continents. Analysis also informed that plate tectonics began around three billion years ago (tectonic plates are immense structures whose motions can cause earthquakes).

 

"It is astonishing that we can use the smallest mineral grains that can be analyzed to reveal the origin of some of Earth's largest geological features,” said Stephen Richardson of the University of Cape Town.