The Chemical Education Journal (CEJ), Vol. 9, No. 1 (Serial No. 16). The date of issue: April 12, 2006./Registration No. 9-1/Received November 1, 2005.
URL = http://www.juen.ac.jp/scien/cssj/cejrnlE.html


CHRYSOTILE

Name: Chrysotile
Occurs in: Carifornia, USA
Width of Picture: about 160 micrometers
Chemical Formula: Mg3(Si2O5)(OH)4

This SEM photograph shows fibrous chrysotile called white asbestos becoming a social problem now. Chrysotile, which is one of serpentines, occurs in serpentinite derived from the alteration of peridotite. There are three main types such as chrysotile, lizardite and antigorite in serpentine. Chrysotile occurs in the form of needles, and lizardite and antigorite are tabular in shape. When we breathe a chrysotile needle less than 1 micrometer in size, it sticks to the lung cell. Furthermore, it is absorbed by these cells. It is assumed that it is the cause of mesothelioma.

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Takanobu Oba
Geoscience Department, Joetsu University of Education
E-Mail:ohba@juen.ac.jp
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