Silicate minerals all contain silicon and oxygen -- the two most abundant elements in the Earth's crust. Silicates are by far the more abundant of the two groups of minerals, comprising some 75 percent of all known minerals and 40 percent of the most common minerals. Virtually all igneous rocks are made from silicate minerals; most metamorphic and many sedimentary rocks are made from silicates as well. They can be subdivided into smaller groups on the basis of their structure.
Silicates are divided into different groups based on their structure. The first of these is the neosilicates, which are formed from atoms arranged in four-sided shapes called tetrahedra, with four oxygens on each unit that can connect with atoms arranged in other shapes containing positively charged ions cations like aluminum or potassium.
Sorosilicates have units of two tetrahedra that share one oxygen atom, while cyclosilicates have rings of tetrahedra, each tetrahedron sharing two oxygen atoms with its neighbors.
Cations can become trapped in the center of these rings. Inosilicates have continuous chains of tetrahedral units, each of which shares two oxygens with its neighbors. Phyllosilicates have sheets of tetrahdra, each of them sharing three oxygens with immediate neighbors; the sheets are separated by other groups and arrangements, and cations can be trapped in the spaces between tetrahedra. Finally, tectosilicates have a continuous framework of tetrahedra, each sharing all four oxygen atoms with its neighbors.
This is because the oxygen atoms around the silicon atom are in the shape of a tetrahedron. Silicate minerals are the rock-forming minerals. There are different types of silicate minerals that can be found naturally. Some of these types are Nesosilicates or orthosilicates, Sorosilicates, Cyclosilicates, etc. These minerals are different from each other according to the arrangement of the silicon-oxygen tetrahedron.
However, the silicate minerals fall into four major groups. Some common examples of silicate minerals are quartz, feldspar, olivines and garnet minerals. Quartz is a common mineral that can be found on the earth surface. For example, rocks, sandstones are all made out of quartz. Silicate minerals are very useful resources for many industrial productions. For example, quartz is used in the production of glass, computers, etc. Clay is important in the production of pots and other household needs.
Most importantly, weathering of these silicate minerals forms the soil on earth. Nonsilicate minerals are minerals that are not composed of silicate groups. These minerals may contain oxygen atoms but not in combination with silicon.
It is classified into six classes such as oxides, sulfides, carbonates, sulfates, halides, and phosphates. These minerals are quite valuable and have wide usage. Examples of non silicate minerals are gold, platinum, and silver. They are used in the formation of diamonds and rubies among other valuable gems. The core difference between silicate and nonsilicate minerals is that silicate minerals occur in abundance and have silicate groups while nonsilicate occur in less abundance and do not have silicate groups.
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