From a ranch the oldest crystal also the oldest piece of earth found in a sheep ranch. This crystal is a translucent red, Valley said, but glows blue when bombarded with electrons. The crystal was found in an arid region north of Perth, Australia, in a low range of hills called the Jack Hills, in 2001. "What we've learned is that the Earth cooled much more quickly that people had thought," Valley said. "The surface formed a crust much more quickly than people thought." Our planet is thought to be about 4.54 billion years old, but the entire fossil record only goes back 600 million years. That doesn't necessarily mean that no life existed before that time, but no direct evidence has been found yet. The standard method of dating such rocks involves looking at the radioactive decay of uranium atoms to lead. But if the lead has moved within the crystal over time, this could lead to a faulty estimate of age. If lead has migrated away from the area of the rock being tested, that could make the rock appear younger than it is, or older if lead has concentrated itself.
It always amazes me, how much we think we know about our planet, that we really don't. We discover new things day by day and it is amazing. I can not wait to see what else we discover about earth in our future.
I love learning about the history of our planet. I find it intriguing to take back the earth to before our human race was developed. It puts us in perspective to other planets and the beginnings of other solar systems.
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