Geological and economic evaluation is not only the most important part of geological exploration, but also the main content, its meaning and essence. Any search, any exploration should be completed by determining the quantity and quality of identified mineral reserves, the possible annual volume of production, the necessary capital investment for the construction of the mine, its economic efficiency ...

In the term “stage” is invested different volume and content. The most justified representations of A.D.Shcheglov and D.O.Ontoev, according to which the stage should be determined by a set of features: the presence of intersections; crushing of formations of early stages and cementation of them with the substance of later stages; interstage dykes of intrusive rocks; temperature of mineral formation; paragenesis of minerals ...

Integrated use of minerals is the most important means of their careful consumption, reducing losses in the subsoil, prolonging the life of mines and, accordingly, more fully meet the needs of social production. At the same time, the mining industry is concentrated, capital investment is saved, and the total cost of labor, time, and money for mining is reduced. ...

Only 50 years ago in the world were known single massifs composed of the original complex of ultramafic-alkaline rocks and carbonatites. Now there are more than 200 of them, and it should be expected that their number in the coming decades will increase significantly. The search for and study of such massifs are increasingly expanding both in the USSR and abroad, mainly due to the discovery of large and sometimes unique deposits of tantalum-niobates, iron, apatite, phlogopite, etc.

The most important indicators of mica deposit conditions are minimum commercial and cutoff grades. Up to now all calculations of mica (phlogopite and muscovite) reserves have been carried out according to Glavsluda conditionals of the USSR Ministry of Railroads, introduced in 1950. For deposits of phlogopite and muscovite these conditions provide the following content of broken mica per minimum excavation thickness of veins, equal to 1 m, kg • cm²/m³.

In the practice of calculation of reserves the rule has taken root that if there is a correlation between the content of a useful component and some other parameter, the average content should be determined by the weighted average method, and if there is no correlation - by the arithmetic mean method. This point of view was first expressed by N. V. Volodomonov and later supported by P. L. Kallistov, V. I. Smirnov, V. M. Kreuter, V. I. Kuzmin and others. However, N. F. Zalata and A. A. Petrov strongly argue that the weighted average method is erroneous and recommend that the average content be determined only by the arithmetic mean method. In the last paper L. F. Zalata connects the method of determining the average content with the type of asymmetry of the distribution of the useful component. V. I. Borzunov believes that the weighted average method is applicable only in the case of changes in content along a hyperbolic curve. In other cases he recommends to apply the method of arithmetic mean. V. A. Petrov proves that the weighted average method of determining the average content in the predominant number of cases gives a more satisfactory result than the arithmetic mean method. Experimental studies carried out on models of ore bodies by I. A. Zimin and E. A. Zimin and E. M. Teplyakov, have shown that in some cases weighted average, and in other cases - arithmetic mean methods of determining the average content of ...

Conditions - a set of requirements set by the industry to the quality of mineral raw materials and mining and geological parameters of the deposit during delineation and calculation of reserves in the subsoil, compliance with which is achieved the correct division of reserves into balance and off-balance reserves. Under balance reserves according to the Classification are understood such reserves, the use of which is economically feasible, and under off-balance reserves - reserves, the use of which at present is not economically feasible, but which in the future may become the object of industrial development....