A mineral is an inorganic and solid substance that occurs in nature. It is represented by chemical formulae. Normally a biogenic mineral is one whose atomic structure has an ordered pattern.
Types of minerals
The major part of the Earth’s crust is filled with oxygen and silicon; therefore the essential group of minerals connected with varieties and formation of rocks is to a great extent, the silicate elements. Still, minerals belonging to the non-silicate group have much economic significance like the ores.
Minerals of the non-silicate group are further classified into many groups according to the chemistry that governs them. They are comprised of the local elements, such as oxides, sulfides, hydroxides and halides, nitrates and carbonates, sulfates, borates, phosphates and also organic compounds. Most of the species of non-silicate minerals are very rare (comprising of a total of 8% of the crust of the Earth.) A few of the non-silicate species are comparatively widespread, like pyrite, calcite, hematite and magnetite. From among the non-silicates, there exist two prominent configurations seen in their structure: Tetrahedral such as silicate and closely-cramped structures. The closely-cramped structures that lead to densely cramped atoms have their interspaces reduced.
Hexagonal close-packing or dense cramping entails piling up of alternate identical layers (“ababab”), but, cubic close-packing consists of piling layers in groups of three (“abcabcabc”). Same as linked silica, tetrahedral involves PO4 (phosphate), SO4 (sulfate) VO4 (vanadate) and AsO4 (arsenate). As far as economy is concerned, the non-silicate elements are of immense significance, since their concentration of the elements is greater than the silicate minerals.
The silicates are, to a great extent the biggest class of elements, The majority of rocks constitute more than 95% silicate minerals; further, more than 90% of the crust of the Earth constitutes of these minerals. Oxygen and silicon are the two main elements in the silicates. These are the two elements found in abundance in the crust of the Earth. The other normal elements found in the crust of the Earth have relevance to the other normal elements in silicate minerals such as magnesium, aluminum, calcium, iron, potassium and sodium. A few of the essential silicates that form rock are garnets, Feldspars, Olivines, Micas, Amphiboles and Pyroxenes.
What discriminates Non-Silicate Minerals from Silicate Minerals?
Non-Silicate minerals are deficient of the combination of oxygen and silicon. But, Silicate minerals have the structure SiO which is chiefly the composition of oxygen and silicon atoms.
When compared to Non-Silicate minerals, Silicate minerals are found in enormous amounts in the crust of the earth.
Non-Silicate minerals are not so complicated as Silicate minerals
Non-Silicate minerals are mainly found as ore minerals, whereas Silicate minerals are minerals that form rocks.
Some Silicate minerals and their uses
Mineral Chemical formula The type of rocks that they are commonly found within How People Use Them:
Olivine (Mg, Fe) 2SiO4 Ultramafic igneous rocks A gemstone
Pyroxene group (Mg, Fe) SiO2 Basaltic igneous rocks
Amphibole group (example: hornblende) (Ca2Mg5) Si8O22 (OH) 2 Andesitic igneous rocks
K (Mg, Fe) 3Si3O10 (OH) 2
KAl3Si3O10 (OH) 2 Andesitic igneous ocks Colonial Americans substitute mica sheets for their window glass.
Feldspars Articles: KAlSi3O8
(Ca, Na) AlSi3O8 Granitic igneous rocks Essential in the manufacture of glass and ceramics
Quartz SiO2 Granitic igneous rocks Quartz is the ingredient in the manufacture of glass and used in clocks to keep.
Olivine resembles tiny crystals, green in color, naturally obtained in certain metamorphic and igneous rocks. 2These crystals are generally so tiny, that in order to have a clear vision of them you require a magnifying glass or a hand lens
We generally find pyroxene minerals in basalt, extruded from the igneous rocks and in meteorites. Pyroxene exists in diverse varieties such as Wollastonite, Enstatite, Augite, Diopside and Hypersthene. Si2O6 exists in all these varieties, but a few contain sodium (Na) and the remaining contains magnesium (Mg), Iron (Fe), or these three elements combined together.
The amphibole family is comprised of many diverse minerals, however the usual variety is Hornblende. Tiny crystals of hornblende are found in several varieties of igneous rocks. Frequently they appear as tiny dark specks. You require a magnifying glass or a hand lens to have a view of the shape of the crystal.
Some rocks are glittered by Mica minerals! Frequently we see them in igneous rocks like Metamorphic and Granitic rocks like schist. They glitter on account of the light that is reflected on the plane surfaces which is the place where the minerals crack along the cleavage plane. These minerals crack with such ease all along their cleavage, such that few of them shatter into thin layers, which appear like the pages of a tiny book. These “pages,” obtained from big crystals of mica were used by the Colonial Americans in place of glass for windows.
The frequently obtained mineral in the crust of the Earth has been Feldspar, as such; there is all chance of you finding them in the rocks you get! You find them in all the three varieties of rocks, however, very often in intruded igneous rocks, such as granite, that appear pink or white in color
In the crust of the Earth, the mineral that is very common is Quartz!
Oxygen (O) and Silica (Si) are the lone two elements contained in pure quartz. In case silica is the residue that remains when the magma cools, in the formation of feldspars, then it is likely that quartz is formed.
Some non silicate minerals and their uses
Mineral Group Example Mineral How People Use Them
Oxides Hematite (Fe2O3)
(Magnetite is another type of oxide!) Ore of iron
Sulfides Pyrite (FeS2) Called fool’s gold
Sulfates Gypsum (CaSO4 (+2H2O)) A component in the manufacture of plaster
Halides Halite (NaCl) Used as table salt
Carbonates Calcite (CaCO3) A component in the manufacture of cement
Native Elements Sulfur (S) An element contained in chemicals and drugs
Magnetite is a naturally occurring magnet! In the family of oxides, The normal way of recognizing a magnetite is through its deep color and intense magnetism.
The color of pyrite is brassy yellow, similar to that of pure gold. However, pyrite does not fetch a high price as Gold. The reason being it is a mineral commonly available; it is seen in all the three varieties on rocks, igneous, sedimentary and metamorphic.
Gypsum is obtained in deserts, sedimentary rocks and caves. Gypsum is abundantly formed in layers in the bottom of a lake or on the salty sea, following the evaporation of water, and gypsum is left as a residue.
What’s on your chips? Nothing but the mineral named halite! In case you have a close glance at your home table salt, it appears to you, similar to other minerals, with the appearance similar to crystals. Halite is nothing but salt. In the originally obtained form we call it rock salt.
We find Calcite specific in the sedimentary rock named limestone. Besides calcite is seen in marble, which is also a metamorphic rock, formed when you heat limestone subjected to high pressure and heat.
What's that smell?
When mineral sulfur is mixed with water, a chemical reaction takes place and a little quantity of hydrogen sulfide (H2S) gas is formed. The smell of Hydrogen sulfide gas is similar to that of the bad smell of rotten eggs. That's the cause of the nasty smell!