Difference Between Quartz and Feldspar (With Table)

Minerals are found abundantly on Earth’s crust. Around sixty per cent of the crust is filled with Feldspars. However, quartz is found on the lithosphere prominently as well. Feldspar and Quartz are sometimes confused by some people because they possess similar structural characteristics. These two minerals are highly crucial rock-forming minerals.

Hence, this article highlights the key differences between the two minerals, feldspar and quartz. Both of these minerals contain atoms of silicon. However, they also contain oxygen atoms. They differ from each other in terms of their composition. The major element in quartz is atoms of silicon. On the contrary, it is aluminium in the case of Feldspars.

Quartz vs Feldspar

The main difference between quartz and feldspar is that Silicon is Quartz’s most important ingredient or chemical element. However, on the contrary, Aluminium is the most abundant ingredient or chemical element in Feldspar. Moreover, they both are types of chemical compounds and highly beneficial for mankind. They are used in various chemical and mechanical industries.

Quartz is a kind of mineral composed primarily of oxygen and silicon atoms. SiO4 is the fundamental unit that repeats itself to make the entire quartz. Feldspar’s texture is softer than quartz. Quartz is often white. The hexagonal form of the crystal system. Because of its piezoelectric capabilities, quartz is widely employed in the gemstone and electronics industries.

Feldspar is a kind of mineral compound that mostly consists of oxygen, aluminium, and silicon atoms. Feldspar’s repeating unit is KAlSi3O8 – NaAlSi3O8 – CaAl2Si2O8. Feldspar is a less hard mineral than Quartz. Feldspar comes in a range of colours, including purple, brown, and others, due to impurities. The system’s crystal structure is triclinic and monoclinic. Feldspar is commonly utilised in the ceramic and glass industries.

Comparison Table Between Quartz and Feldspar

Parameters of Comparison

Quartz

Feldspar

Definition

A type of mineral compound that contains mainly atoms of Oxygen and Silicon.

A type of mineral compound that mainly contains Aluminium, Oxygen and Silicon atoms.

Major constitution

Silicon

Aluminium

Hardness

Harder than Feldspar.

Less hard than Quartz.

Use

Gemstones and electronic industry.

Ceramic and glass industries.

Primary repeating unit

SiO4

KAlSi3O8 – NaAlSi3O8 – CaAl2Si2O8

Appearance

Light coloured in appearance.

Found in a variety of colours, including purple, brown, etc., as impurities are present.

Shape of Crystals

Hexagonal in shape.

Triclinic and monoclinic in structure.

What is Quartz?

Quartz is a mineral composition made up primarily of oxygen and silicon atoms. Silicon is the most common ingredient or chemical element in Quartz. SiO4 is the fundamental unit that repeats itself to make the entire quartz. The texture of Quartz is tougher than that of Feldspar.

Quartz is typically a light-coloured stone. The hexagonal crystal system has a hexagonal form. Because of its piezoelectric qualities, quartz is widely employed in industries such as gemstones and electronics. Quartz is a type of mineral that is found on the earth crust in abundance.

In Quartz, its chemical structure comprises four oxygen atoms and one silicon atom, where they are bonded to each other. Thus, this whole set-up makes the shape tetrahedral in geometry. However, two tetrahedral molecules share one oxygen atom. Hence it becomes hexagonal in geometry.

What is Feldspar?

Feldspar belongs to a family of mineral compounds that are mostly made up of oxygen, aluminium, and silicon. Aluminium is Feldspar’s most important ingredient or chemical element. KAlSi3O8 – NaAlSi3O8 – CaAl2Si2O8 is the Feldspar repeating unit.

Compared to Quartz, Feldspar is a softer mineral. Because impurities are present, feldspar can come in a range of colours, including purple, brown, and others. The triclinic and monoclinic structures of the system of crystals are both present. The ceramic and glass industries rely heavily on feldspar.

In feldspar, silica and alumina units are combined. This mineral is formed when the magma solidifies inside the earth crust and forms igneous rocks. However, the same occurs in the other two types of rocks as well, i.e., sedimentary and metamorphic rocks.

Main Differences Between Quartz and Feldspar

  1. Quartz is a type of mineral compound that contains mainly atoms of Oxygen and Silicon. On the other hand, Feldspar is a type of mineral compound that mainly contains Oxygen atoms, Aluminium atoms and Silicon atoms.
  2. The major constituent or chemical element of Quartz is silicon. On the other hand, the major constituent or chemical element of Feldspar is Aluminium.
  3. The primary unit that repeats itself to form the whole quartz is SiO4. On the other hand, the repeating unit of Feldspar is KAlSi3O8 – NaAlSi3O8 – CaAl2Si2O8.
  4. Quartz is comparatively harder than the texture of Feldspar. On the other hand, Feldspar is comparatively less hard than Quartz.
  5. Quartz usually looks light coloured in appearance. On the other hand, Feldspar is usually found in a variety of colours, including purple, brown, etc., as impurities are present.
  6. The shape of the system of crystals is hexagonal. On the other hand, the structure of the system of crystals is triclinic and monoclinic in structure.
  7. Quartz is used abundantly in industries related to gemstones and the electronic industry, as it possesses piezoelectric properties. On the other hand, Feldspar is used abundantly in the ceramic and glass industries.

Conclusion

Minerals can be found in abundance throughout the Earth’s crust. Feldspars account for approximately 60% of the crust. Quartz, on the other hand, is abundant in the lithosphere. Some individuals get confused between feldspar and quartz because they have similar structural features. These two minerals are extremely important in the formation of rocks.

As a result, the fundamental differences between the two minerals, feldspar and quartz, are highlighted in this article. Silicon atoms can be found in both of these minerals. They do, however, include oxygen atoms. In terms of composition, they differ from one another. Silicon atoms make up the majority of quartz. Feldspars, on the other hand, are made of aluminium.

References

  1. https://www.sciencedirect.com/science/article/pii/S0191814103000816
  2. https://www.sciencedirect.com/science/article/pii/0040195178900975