-The paper observes matter about identification of zone with a stable value of gradient in Faraday's balance. This matter is solved by purpose obtained coordinate characteristics of magnetic field induction between pole pieces of such balance. The paper shows that such identification may be quite effective when given characteristic (usually it is non-linear and doesn't yield to desired linear even local approximation) is curly, i.e. has an inflection. It is possible to make a linear approximation of rather shortly characteristic's region, i.e. establish a stable values of induction pole gradient. It is also possible to get visualized extremum view of gradient induction characteristic: in the vicinity of its extremum gradient value are relatively stable.

The model of operational-functional magnetic control of ferroimpurities is physically substantiated and implemented. In this research the relevant (consistent with the phenomenological) calculation formulas were obtained to determine the total mass of ferroimpurities (including the residual one) in the analyzed sample. In addition to the mass-operational characteristics of magnetic control, the corresponding total accumulative characteristics (including in a generalized form) were obtained and analyzed, confirming validity of the model used.