Often found in the popular science literatureterms "minerals" and "rocks". 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 what the minerals differ from rocks.
Minerals
In order to find out the difference between a mineralfrom a rock formation, 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. The structure can be compared with glass.
Mineral classification
Scientists have about 2500 minerals, which have their own varieties. The chemical elements that make up the minerals are divided into several groups:
- Native elements - crystalline substanceslattice which 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 a different crystal structure. At the same time, diamond is a standard of strength, and graphite, on the contrary, is very soft. This group includes about 90 minerals.
- Сульфиды – минералы, кристаллы которых состоят из sulfur and metals or non-metals. For example, galena, sphalerite. Interesting fact: the mineral pyrite has the second name "fool's gold". This is due to the fact that externally pyrite in color and metallic luster is similar to a precious metal. This group includes about 200 minerals.
- Sulfates - 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, the screens in the X-ray rooms consist of that mineral, and the walls are covered with barite plaster. The group includes about 260 minerals.
- Halides are the minerals formed as a result ofcompounds of different chemical elements with halogens. For example, fluorite, sylvin, halite. Interesting fact: the Roman emperor Nero had a weakness for fluorite, buying products from it for very big money. The group includes about 100 minerals.
- Phosphates - natural salts of phosphoric acid.For example, vivianite, purpurite, apatite. Interesting fact: turquoise is the most beloved gem of the Persians. The cost of some copies is 3-4 times higher than the price of gold. The group has about 350 minerals.
- Carbonates are natural salts of carbonic acid.For example, calcite, dolomite, magnesite. An interesting fact: the massif of the Alps includes an array called the Dolomites, because dolomite is a part of the rocks. Mountains when exposed to sunlight on them become pink.
- Oxides - the minerals formed as a resultcompounds of metals and oxides. For example, alexandrite, flint, opal. Interesting fact: Ametrine is one of the rarest on the planet. Its peculiarity is that the drawing of a precious stone is unique, each new copy differs from the previous one. The group has about 200 minerals.
- Silicates are the most extensive group of minerals, inThe composition of which includes silicon, aluminum. For example, topaz, plagioclase, serpentine. An interesting fact: earlier, even before the invention of glass, mica plates were inserted into the windows.
Now, in order to see the difference and differences between rocks and minerals, let’s analyze the first named concept.
Rocks
Minerals are not found in the earth's crustspecimens. As a rule, under the influence of external factors, they combine to form rocks. Thus, minerals differ from rock in that they are its composite brick. But not all minerals are involved in rock formation. Therefore, scientists divide them into rock-forming (mostly silicates) and additional ones.
Rock classification
For a clearer understanding than the minerals differ from the rocks, let's analyze the formation of the latter. Geologists distinguish three groups of rocks along the path of their origin:
- Igneous formed as a result of outpouringmagmas in the earth’s column or on the surface (volcanoes). They are the primary rocks, of which as a result of various environmental influences the rocks of the two remaining groups were formed. For example, granite, basalt, gabbro.
- Metamorphic formed as a resulttectonic movements of the earth's crust. This means that sedimentary rocks and magmatites once again found themselves in the earth’s strata and there, under the influence of high temperatures and pressures, they were transformed into new rocks. For example, gneisses, slates, marble.
- Sedimentary rocks account for only 10%. They are formed as a result of the actions of wind and water on the magmatites located on the surface of the Earth. For example, eluvium, deluvium, alluvium.
The formation of rocks and minerals is an inseparable process. We have determined how minerals differ from rock, and we can confidently say that these components of the earth's crust are interconnected.
