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Article: The importance of bioactive silicates in human health.
- Article from:
- Original Internist
- Article date:
- March 1, 2005
- Author:
CopyrightCOPYRIGHT 2005 Original Internist, Inc. This material is published under license from the publisher through the Gale Group, Farmington Hills, Michigan. All inquiries regarding rights should be directed to the Gale Group. (Hide copyright information)
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Introduction
The element silicon does not exist in nature in its pure form but rather is always combined with oxygen. Next to oxygen, silicon is the most abundant element in the earth's crust. Silicon dioxide or silica, Si[O.sub.2], is formed by covalent binding of two atoms of oxygen to one atom of silicon. Free silica is found both in the amorphous state such as opal and in the crystalline state such as quartz. Biological systems are capable of forming amorphous microparticles of hydrated silica, but they cannot form the crystalline state of silica. Under proper conditions, one molecule of silica will react covalently with one molecule of water to form ...