ErikPeter (![[info]](http://l-stat.livejournal.com/img/userinfo.gif){kind=small} voxen) wrote,@ 2009-05-04 13:33:00 |
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nature is cool
From Nature's Building Blocks (John Emsley):
Francium occurs naturally in uranium minerals, but there is only one francium atom per billion billion (1018) atoms of uranium. These few atoms of francium-223 are there as the radioactive decay product of actinium-227, which in turn is part of a uranium-235 decay series. The short half-life of francium-223 means that there is probably less than 30 grams of francium in the Earth's crust at any one time.
From Nature's Building Blocks (John Emsley):
Francium occurs naturally in uranium minerals, but there is only one francium atom per billion billion (1018) atoms of uranium. These few atoms of francium-223 are there as the radioactive decay product of actinium-227, which in turn is part of a uranium-235 decay series. The short half-life of francium-223 means that there is probably less than 30 grams of francium in the Earth's crust at any one time.
