Question

What silicate mineral is the basic building block of many rocks?

Answer 1

Hint: Silicate means the compounds contain a high number of silicon atoms and oxygen atoms. The building block of rock contains silicates in which silicon, oxygen, aluminium, calcium, and other alkali metals are present.

Complete answer:
Rocks are the substances that are present in the crust and mantle layer of the earth, and the rocks are responsible for the formation of soil. These rocks are hard substances and made up of minerals. The most elements present in the rocks are silicon, oxygen, and some metals.
The building block of rock contains silicates in which silicon, oxygen, aluminium, calcium, and other alkali metals are present. So, this is known as Feldspar. Since silicates are a type of polymer in which repeating units are present and Feldspar is a Tectosilicate. The formula of repeating unit of Feldspar is $KAlS{{i}_{3}}{{O}_{8}}-NaAlS{{i}_{3}}{{O}_{8}}-CaA{{l}_{2}}S{{i}_{2}}{{O}_{8}}$.
There is another silicate that is also present in a very large amount known as Olivine and Olivine is a silicate of magnesium and iron. Not only in rocks and earth, but silicates are also present in the entire universe.
The Feldspar is $KAlS{{i}_{3}}{{O}_{8}}-NaAlS{{i}_{3}}{{O}_{8}}-CaA{{l}_{2}}S{{i}_{2}}{{O}_{8}}$, and it has three parts:
$KAlS{{i}_{3}}{{O}_{8}}$ is potassium feldspar endmember
$NaAlS{{i}_{3}}{{O}_{8}}$ is albite endmember
$CaA{{l}_{2}}S{{i}_{2}}{{O}_{8}}$ is anorthite endmember
The crystal structure of Feldspar is triclinic or monoclinic. Its color ranges from white, grey, brown, and blue.

Note:
Around 41% of the earth’s crust is made up of tectosilicate minerals or Feldspar by weight. It is found in igneous rocks as well as in many types of sedimentary rocks. There is another type of feldspar other than alkali feldspar, i.e., Barium feldspar.