## 4 Two-Phase Media  
The use of GALVI technology in natural building stones requires knowledge of the stone composition and its deterioration by microorganisms. Earlier microbiologists isolated microorganisms and cultivated them on artificial one-phase media afterwards [13; 25; 37; 86]. [PERSON] & [PERSON] [87] observed the autotrophical growth of _Cephalosporium_ sp. and _Fusarium_ sp. on a medium devoid of any known organic carbon source. Recently started experiments with media would allow us to observe the development of fungi in a two-phase environment. These two-phase media were used with SNA (synthetic low-nutrient agar) medium + sterile grandiorite1, melabasanite2, sandstone3, marl4, and sodium glass (as control). Microorganisms inhabit the boundaries of two liquid and solid phases. This enables the investigation of the processes of colonization, course, and development of selected microorganisms in the emerging rock microhabitats (Figure 7). Two-phase media with granodiorite and sandstone were much more colonized by fungi than media with melabasanite and marl. Both marl and melabasanite have a lower porosity and higher content of Ca; moreover, melabasanite is dark, has a low water absorption, high pH (45% SiO2), and contains toxic Fe (see Figure 5). In addition, melabasanite can be a good habitat for special microorganisms that, in addition to Ca, still require Mg, Fe, and/or Al [88; 89; 90]. The content of elements in the mentioned rocks is very rich, and possible interactions between cations and anions during changing pH are difficult to interpret. For example, a ferric hydroxide can be created at pH > 4.5, whereas poor coagulation occurs in the pH range between 7 and 8.5 [91]. The influence of environs on cations' toxicity was mentioned earlier by [PERSON] [85]. Metal transformations were thoroughly described by [PERSON] [92]. Granodiorite is a light gray igneous acidic rock, the main components of which are quartz (SiO2), potassium feldspar (KAlSi3O8), sodium plagioclase (Na[AlSi3O8]), and biotite (K(Mg,Fe2)3(OH,F)2 AlSi3O10). The average analysis of the chemical composition shows the dominance of silica (71-74%), followed by large amounts of aluminium (12-16%) and smaller but significant amounts of sodium (3-4%) and potassium (2-3%). Figure 7: Fungi growing on SNA medium after two months: (**A**)—marl, (**B**)—melabasanite, (**C**)—granodiorite, and (**D**)—sandstone, photo A. [PERSON]. **2. ** Melabasanite (with a transition to ankaratrite) is a dark volcanic rock belonging to ultrabasic rocks (<45% SiO\({}_{2}\)). The main minerals are pyroxenes (Ca silicates, Mg and Fe silicates), olivines (Mg,Fe)\({}_{2}\)[SiO\({}_{4}\)], amphiboles (hydrated Ca-silicates, Mg, Fe, and Na), and calcium plagioclase Ca[Al\({}_{2}\)Si\({}_{2}\)O\({}_{8}\)]. In a variety closer to ankaratrite (a type of nephfinite), one of the main minerals is nepheling (sodium and potassium aluminosilicate (KNa\({}_{3}\)(AlSiO\({}_{4}\))\({}_{4}\)). The average chemical composition analysis shows, apart from silica (40-42%), large amounts of aluminium (13-14%), iron (approx. 12%), magnesium (approx. 12%), calcium (10-12%), and significant amounts of sodium (3-4%). **3. ** Sandstone is a coarse-grained beige clastic rock in which the spaces between quartz grains (SiO\({}_{2}\)) are filled with silica-iron-clay binder (SiO\({}_{2}\)/Fe\({}_{2}\)O\({}_{3}\)/hydrated aluminosilicates). Its technical parameters are variable, depending on the content of Fe\({}_{2}\)O\({}_{3}\). Therefore, the main components of this sandstone are silica, aluminum, and iron. **4. ** Marl is a pale beige sedimentary rock with variable proportions of two main components: calcite (CaCO\({}_{3}\)) or dolomite (CaMg(CO\({}_{3}\))\({}_{2}\)) in the amount of 50-75% and clay minerals (hydrated aluminosilicates) in the amount of 25-50%. Marl may also contain 0-50% SiO\({}_{2}\). Its main components are therefore calcium, aluminium \(\pm\) silica. This was elaborated on the basis of the following books: [93; 94; 95].