Science and Health

Crystal Confirmed As Oldest Known Piece of Earth

Scientists say the finding confirms their theory on how Earth cooled and became habitable.

Crystal Confirmed As Oldest Known Piece of Earth
University of Wisconsin / John Valley

On a sheep farm in Australia — scientists from the University of Wisconsin have found what they believe is the oldest piece of Earth ever discovered. 

"Here it is, a zircon crystal 4.4 billion years old. That's almost as old as the earth itself which is thought to be 4.5 billion years old." (Via CBS)

The crystals are thought to have formed just millions of years after our planet was only a ball of molten rock — much too hot to support life or even land masses. (Via History Channel

The study's lead researcher, professor John Valley, said in a statement, "This confirms our view of how the Earth cooled and became habitable... This may also help us understand how other habitable planets would form.” (Via University of Wisconsin)

The zircon crystals are so tiny, if you were holding one in the palm of your hand you wouldn't even know it without a microscope. They come in all different shapes and can be completely transparent all the way to a deep red color. 

According to researchers, Jack Hills in Western Australia, the sheep farm where the crystals were found was actually a beach about 3 billion years ago. The scientists say even then the crystals were merely a speck of sand. (Via NASA)

Now, the position of the atoms in the crystals is how the researchers determined their age, but some critics say it's possible those atoms could have shifted — making the crystal appear older than they actually are. But the study's lead researcher explained to NPR his team was able to confirm the age using an instrument that can extract atoms from the crystals. 

And a geologist at the Massachusetts Institute of Technology backed up the method, "I think people will be impressed with the technique and impressed with the conclusions and agree with them... Now we're talking about a history on this planet that goes back to almost the day that the planet was born."

Valley's team is now using that technique to look at zircons from the moon brought back from the Apollo astronauts. The hope is one day they will stumble over a larger form of a zircon that dates back just as far, if not farther than the new findings.