Concepts: mineral, ore, mineral species. Minerals are crystalline substances, homogeneous in composition and structure, formed as a result of physical and chemical processes and being a part of rocks and ores. From a chemical point of view, a mineral is a more or less homogeneous body, corresponding to a certain composition. Physically, each mineral is also characterized by more or less limited qualities: hardness, density, magnetality, optical properties, etc.
To define the concept of "mineral" it is necessary to make the following remarks.
- We will conditionally refer to minerals not only obviously crystalline substances, but also some latent crystalline and amorphous natural substances (chalcedony, agate, opal and some others), which belong to the kingdom of minerals. They are also solids, products of natural processes, components of rocks and ores.
- Minerals should include natural chemically and structurally homogeneous formations that are parts of other cosmic bodies - the Moon, planets, meteorites. Thus, we can talk about the mineral composition of lunar rocks, the mineral composition of stone meteorites, etc. It is interesting to note that some minerals known in meteorites are not known on Earth (for example, calcium sulfide - oldgamite CaS or iron phosphide, nickel and cobalt a - shreiberzite (Fe, Ni, Co)3P).
- Different synthetic products with similar properties, composition and structure to minerals are called artificial minerals. These are, for example, artificial quartz, corundum, mica, etc. obtained in the laboratory.
The distribution of minerals in nature is extremely wide. The entire Earth's crust, all rocks and mineral deposits consist of minerals.
The size of mineral individuals can range from large ones, weighing several tons (feldspar, quartz), to the smallest grains visible only in the microscope. Most minerals are found in the form of small and tiny grains, forming a granular structure of magmatic, sedimentary and metamorphic rocks.
There are about 2200 known minerals, and the number of their names with more than 4000 varieties. The latter is explained by the fact that many minerals have several names (synonyms). Besides, the varieties of minerals get their own names due to deviations from chemical composition, color and other properties. There are about 450 widely spread minerals in the nature, the rest are rare.
The names of minerals are given by their characteristic physical properties, their chemical composition or the place where they were first discovered. Many minerals are named after scientists who discovered or described them.
Minerals as minerals are also found in the Crimean peninsula. Nowadays about 200 species and varieties of minerals (about 8% of the known minerals in the world) are discovered and studied.
Rocks and minerals found only in the Crimea are described in his work "With a geological hammer through the Crimea u" Vladimir Lebedinsky.
A few kilometers to the right from the main road to Kerch, the highway to the village of Arshintsevo - the starting point of the excursion. The village of Kamysh-Burunskiy Iron Ore Plant miners is a well planned town on the shore of the Kerch Strait. Previously it was called Kamysh-Burun, and after the liberation of the Crimea from the Nazi invaders it was named after General B. I. Arshintsev, who died in 1943 at the Kerch bridgehead.
We will start acquaintance with minerals and ores of the deposit with the shoreline precipice of the Kerch Strait in Arshintsevo. From the center of the village we will pass through the park of culture and rest and then we will go down the stairs to the beach. Before us is a high and steep coastal slope, in many places disturbed by landslides and small landslides.
The slope is planned and terraced to strengthen the coast. In the middle part of the slope, layers of various sedimentary rocks are clearly visible. Below all lie the brownish yellow, slightly strong limestone and. They consist of shells of mollusks and their fragments bound together by clay and fine sand. Above lies a dark brown, multi-metre high ore bed, and above it there are layers of grey clays and sands. The upper part of the cliff is composed of light brown loams. What is the age of the sedimentary thickness? It is not difficult to answer this question, as there are various well-preserved fossil shells in the limestone and the ore bed that covers it. It turns out that the limestone belongs to the Pontic tier, while the ore belongs to the Cimmerian tier. These tiers form the upper part of the Neogene system. Thus, the ore bed is geologically very young; its absolute age is only 5-8 million years. In the Cimmerian era of geological history, iron ores were formed in many places of the Kerch Peninsula and in its vicinity on Taman.