Question

Write a note on the minerals which form rocks?​

Answer 1

❤️ Answer :-

Rocks are composed of minerals. A mineral is a naturally occurring substance which is usually solid, crystalline, stable at room temperature and inorganic.

There are almost 5000 known mineral species, yet the vast majority of rocks are formed from combinations of a few common minerals, referred to as “rock-forming minerals”. The rock-forming minerals are: feldspars, quartz, amphiboles, micas, olivine, garnet, calcite, pyroxenes.

Minerals occurring within a rock in small quantities are referred to as “accessory minerals”. Although accessory minerals are present in only small amounts, they may provide valuable insight into the geological history of a rock, and are often used to ascertain the age of a rock. Common accessory minerals are: zircon, monazite, apatite, titanite, tourmaline, pyrite and other opaques.

The abundance and diversity of minerals depend on the abundance in the Earth’s crust of the elements of which they are composed. Eight elements make up 98% of the Earth’s crust: oxygen, silicon, aluminium, iron, magnesium, calcium, sodium and potassium. The composition of minerals formed by igneous processes is directly controlled by the chemistry of the parent body. For example, a magma rich in iron and magnesium will form minerals such as olivine and pyroxene (as found in basalt). Magma richer in silicon will form more silica-rich minerals such as feldspar and quartz (as found in granite). It is unlikely that a mineral will be found in a rock with dissimilar bulk chemistry unlike its own; thus it is unlikely that andalusite (Al2SiO5) would be found in an aluminium-poor rock such as a quartzite.

______❤️Brainliest Please❤️______

Answer 2

Explanation:

The rock - forming minerals are: feldspars, quartz, amphiboles, micas, olivine, garnet, calcite, pyroxenes.

For example : a magma rich in iron and magnesium will form minerals such as olivine and pyroxene { as found in basalt}.

I hope it may help to you..