Si
O

Silicate Bonding — 3

The polymerization of silicates through apical oxygens allows the formation of a number of different silicate structures that form the backbone of silicate minerals, such as:

Highlighting Features

Silicate polymerized to form a chain

as in the mineral jadeite, a member of the pyroxene group

Silicates polymerized to form a ring

as in beryl

Silicates polymerized to form a double chain,

as in the asbestos mineral tremolite, a member of the amphibole group.

Silicates polymerized to form a sheet,

as in kaolinite, a member of the layer silicates, also known as phyllosilicates.

In these structures, all silicon atoms are bonded to four oxygens. In these structures, if the oxygen atoms are not bonded to two silicon atoms, then the second bond is to another positively charged atom, such as Al3+, Ca2+, etc.

The most abundant of the silicate minerals is quartz, SiO2, in which the silicate tetrahedra are not arranged in a single line or plane but instead are regularly arranged in a dense three-dimensional structure, resulting in great resistance to mechanical and chemical weathering.

(Previous: More about Silicate Bonding)

This page is part of the Virtual Museum of Minerals and Molecules. All rights reserved to the Minerals & Molecules Project.
Original release: 4 Oct 2007. Created as course material for UW-Madison Soils 301. Converted from Jmol v11 (Java) to JSmol v14 (javascript/html5) x WordPress: 10 Nov 2016, for the Madison Gem and Mineral Club. Last modified: 10 Nov 2016.
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