One of the main principles of physicochemical analysis—the principle of continuity—says that “continuous change of parameters of the state of the system results in continuous change of properties of individual phases; the properties of the whole system also show continuous changes if no new phases appear and no existing phases disappear” [1]. This formulation does not specify which phases are implied: surface, nonautonomous, or traditional autonomous phases. This problem becomes significant for studying mineral surfaces. Nonautonomous phases (NAP) are nanosized (submicron) surface phases, which are the products of chemical modification and structural reconstruction of surface layers of mineral crystals [2, 3]. They are formed in the crystal surface layer by means of its interaction with components of the growth medium or contacting autonomous phases. Unlike the latter, the nonautonomous phases cannot be extracted from the system without a change in their composition and structures and characteristics of the associated phases. At the same time, their reaction to changes in the state parameters and system composition is different from the reaction of traditional phases, owing to which they can incorporate trace elements, which are incompatible with the structure of the corresponding bulk phase [2]. The aim of this work is to clarify whether the principle of continuity is applicable to the nonautonomous phases and which mineralogical sequences it causes. The study objects are sulfide minerals ascribed mainly to the systems Pb‐S and Fe‐Zn‐S: galena PbS, pyrite, FeS 2 , pyrrhotite Fe 1 – x S , and sphalerite (Zn,Fe)S. Minerals were synthesized by the conventional technique of hydrothermal thermal-gradient synthesis in Ti inserts [3] at temperatures of 400, 450, and 500°C and pressure of 0.5 and 1 kbar both individually and as phase associations containing up to three phases (Fesphalerite + pyrite + pyrrhotite). The mineralizers were either 10% NH 4 Cl, or those with added Na 2 S or HCl (1 wt %) (pyrite synthesis). In some experiments with pyrite, the starting material was enhanced with As (up to 5 wt %), while the starting material for the synthesis of sphalerite and galena contained Cd and Hg sulfides (1 wt % each). Inserts equipped with a self-sealing closure were placed in autoclaves of stainless steel and held for 3 days in an isothermal regime to homogenize the starting material, and then for 7, 9, or 12 days at 500, 450, and 400°C , respectively, at a temperature drop ( 15°C along the outer wall of the autoclave). The experiments were terminated by quenching the autoclave in cold running water. Data previously obtained on the system PbS‐(HgS,CdS) (Cd and Hg sulfides as admixtures) [4] were also used in this work.