Often in the non-fiction literature, the terms “minerals” and “rocks” are used. People who do not have a specialized education do not share these concepts, perceiving these words almost as synonyms. This is totally wrong. Let's see how minerals differ from rocks.
Minerals
In order to find out how the mineral differs from the rock, we consider each natural formation in detail. According to the requirements of the International Mineralogical Association, minerals include solids formed in the bowels of the Earth or its surfaces, having the same chemical composition and crystalline structure.
But not all minerals exactly meet the definition. For example, there are substances that have the same chemical composition, but do not form a crystal lattice, the so-called amorphous minerals (opal). Atoms in such structures are located very close to each other and do not form an ordered system. In this case, the bond between the atoms is quite strong. Their structure can be compared with glass.
Mineral classification
Scientists have about 2500 minerals that have their own varieties. According to the chemical elements that make up the minerals are divided into several groups:
- Native elements - substances whose crystal lattice consists of only one chemical element. For example, sulfur, gold, platinum. An interesting fact: diamond and graphite are minerals consisting only of carbon, but having different crystalline structures. At the same time, diamond is the standard of strength, and graphite, on the contrary, is very soft. This group includes approximately 90 minerals.
- Sulphides are minerals whose crystals are composed of sulfur and metals or non-metals. For example, galena, sphalerite. An interesting fact: the mineral pyrite has the second name "gold of fools." This is due to the fact that externally pyrite in color and metallic luster is similar to precious metal. This group includes approximately 200 minerals.
- Sulfates are natural salts of sulfuric acid. For example, barite, jarosite, gypsum, anhydrite. An interesting fact: barite is the only mineral that can neutralize x-rays. Therefore, screens in X-ray rooms consist of that mineral, and the walls are covered with barite plaster. The group includes about 260 minerals.
- Halogens are minerals formed by combining various chemical elements with halogens. For example, fluorite, sylvin, halite. An interesting fact: the Roman emperor Nero had a weakness for fluorite, buying products from it for a lot of money. The group includes about 100 minerals.
- Phosphates are natural salts of phosphoric acid. For example, vivianite, purpurite, apatite. Interesting fact: turquoise is the most favorite gem of the Persians. The cost of some copies is 3-4 times higher than the price of gold. The group has approximately 350 minerals.
- Carbonates are natural salts of carbonic acid. For example, calcite, dolomite, magnesite. An interesting fact: the Alps mountain range includes an array called the Dolomites, because dolomite is part of the rocks. Mountains when they are exposed to sunlight become pink.
- Oxides are minerals formed by combining metals and oxides. For example, alexandrite, flint, opal. An interesting fact: ametrine is one of the rarest on the planet. Its peculiarity is that the gemstone pattern is unique, each new instance is different from the previous one. The group has about 200 minerals.
- Silicates are the most extensive group of minerals, which include silicon and aluminum. For example, topaz, plagioclase, serpentine. An interesting fact: before the invention of glass, mica plates were inserted in the windows.
Now, in order to see the difference and differences between rocks and minerals, we will analyze the first named concept.
Rocks
In the earth's crust, minerals are not found in single instances. As a rule, under the influence of external factors, they combine to form rocks. Thus, minerals differ from the rock in that it is its composite brick. But not all minerals are involved in rock formation. Therefore, scientists divide them into rock-forming (mainly silicates) and additional.
Rock classification
For a clearer understanding of how minerals differ from rocks, we will analyze the formation of the latter. Geologists distinguish three groups of rocks along the path of their origin:
- Magmatic formed as a result of the outpouring of magma in the earth's thickness or on the surface (volcanoes). They are primary rocks, from which, as a result of various environmental influences, rocks of the two remaining groups were formed. For example, granite, basalt, gabbro.
- Metamorphic formed as a result of tectonic movements of the earth's crust. This means that sedimentary rocks and magmatites again found themselves in the earth's thickness and there, under the influence of high temperatures and pressure, were converted into new rocks. For example, gneiss, slates, marble.
- Sedimentary rocks account for only 10%. They are formed as a result of the action of wind and water on magmatites located on the surface of the Earth. For example, eluvium, deluvium, alluvium.
The formation of rocks and minerals is an inextricable process. We determined how minerals differ from rock, and we can confidently say that these components of the earth's crust are interconnected.