What are Silicates?

What are Silicates?

A member of an ionic compound found in the anion family and containing oxygen and silicon. Silicates are formed from groups of silicates and form rocks. They are the most abundant minerals in the earth's crust, making up 90% of the crust. Due to rework and formation processes, various silicate minerals occur in great combinations on Earth. The processes are diagenesis, weathering, splitting, melting, metamorphosis and crystallisation.

The minerals found on Earth are concentrated by the silicon atom of the tetrahedron, on which are four atoms of covalent oxygen. Additionally, silicates of minerals are grouped into seven groups based on the composition of the silicate ion.

Types of Silicates: Major groups include nesosilicates, sorosilicates, cyclosilicates, inosilicates, phyllosilicates, and tectosilicates.

Types of Silicates

The silicate tetrahedral units consist of silicon and oxygen-containing minerals linked together in multiple patterns. Based on how the tetrahedral units are joined, silicates are classified into the following types:

1. Orthosilicates (or Nesosilicates)

2. Pyro silicate (or Sorosilicates) 

3. Cyclic silicates (or Ring silicates)

4. Chain silicates (or pyroxenes)

5. Amphiboles

6. Sheet or phyllosilicates

7. Tectosilicates

Amphibole Silicate Minerals

Uses of Silicates

Uses of Silicates in Industries like glass, ceramic, cement, etc.

• Glass manufacturing: Glass is made from silicate. This is one of the major and most productive uses of silicate. Formless and hard materials such as clay or sand are burned at high temperatures. The material formed after heating is malleable, so glasses can be made for drinking.

• The use of silicates in ceramics: Silicates are used to make ceramics.  Ceramics made of silicate have thermal characteristics. Therefore, they are a major advantage in the engineering and technology industries.  In one such example, the spacecraft uses ceramic silicate tiles as a barrier from intense atmospheric temperatures.  Silicates also benefit borehole walls when drilling to prevent the walls from cracking.

Use of Silicates in Ceramics

• Microchips: Microchips are a form of silicon cut into small proportions that have controlled printed orders through photographic processes.  Silicates have unique properties, for example, producing thermal insulation, conducting electricity, providing a high-frequency vibration, and being able to conduct electricity.  The most central component of silicates is silicon.  The crystal is very strong and can be cut into smaller sizes, thus conducting electricity.  These properties make silicon the best material for making microchips, passing through computers, mobile phones and gaming devices.

Quartz Uses in Everyday Life

Quartz crystals are silicate with the unique ability to produce a rhythmic high-frequency vibration. For this reason, these crystals are used to make oscillators used in clocks, radios and pressure gauges. The crystal emits a rhythmic beat that when connected to an electronic source and movement pieces can be logged, usually in the form of megahertz (MHz), which is 1 million cycles per second. In the example of a watch, the rhythmic beat of the crystal moves the other hand. Quartz crystals are also used in mysticism.

Quartz Crystals

Why are the Silicates Important?

Silicates occupy about per cent of the Earth's crust and upper mantle, as a major component of most igneous rocks and also in appreciable amounts in sedimentary and metamorphic types. They are also important components of lunar samples, meteorites and most asteroids.

Solved Questions

1. Write the three most important types of Silicates.

Ans: Three important types of Silicates are:

• Orthosilicates (or Nesosilicates)

• Pyro silicate (or Sorosilicates)

• Cyclic silicates (or Ring silicates)

2. Write one use of Quartz crystals.

Ans: Quartz crystals are used to make oscillators in clocks, radios and pressure gauges.

Learning by Doing

Write True or False.

1. Glass is made from silicate.

2. Silicates are the minerals found on Mars.

3. Quartz crystals are used in mysticism.

4. Orthosilicates are ring silicates.

Summary

As we have already read this chapter thoroughly, now we know the actual meaning of silicates and understand their uses and importance in our life. There are many types of silicates found. Some of them are mentioned in this chapter. We have also explained Quartz uses in a separate heading.