Why are some minerals and rocks called minerals?

Mineral resources, mineral formations of the earth’s crust, the chemical composition and physical properties of which make it possible to effectively use them in the sphere of material production. Rocks are called regular stable associations of minerals and other substances (volcanic glass, organic matter) that make up large volumes of the earth’s crust. According to the mineral composition, monomineral and polymineral rocks are distinguished, i.e., consisting mainly of one mineral (limestones, quartzites) or of several (granites, gneisses). The main rock-forming minerals make up the bulk of the rocks. The amount of each of the main minerals should be more than 5%, their presence determines the type of rock. For example, feldspars, quartz and biotite are rock-forming minerals in granite. According to their chemical composition, they are divided into mafic – dark-colored, containing a lot of magnesium and iron, and sialic – light, containing a lot of silicon and aluminum. The mafic group includes olivines, pyroxenes, amphiboles, and micas; to the group of sialic (light) – plagioclases, potassium feldspars, quartz, feldspathoids (nepheline). If the amount of a mineral in the rock is less than 5%, it belongs to the minor. Their presence is not reflected in the general name of the breed. Accessory minerals (Latin additional) are rare minerals. They are found in amounts of less than 1–5%, but often constitute impurities characteristic of rocks (for example, chromite for ultramafic rocks, monazite for granites, eudialyte for nepheline syenites). In addition to rock-forming and minor minerals, xenogenic (alien) or incidental minerals are sometimes present in igneous rocks. They enter the rocks from the outside and are not associated with the crystallization of the magmatic melt.