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Abstract: The concentration of the heavy metals in the soils from the strong affected zones because of the mining and metallurgical industry, Baia Mare and Zlatna (Romania), is significant due to the high values of the contents and association of the four metals Pb, Cu, Zn, Cd. The efficacy of the natural zeolites in heavy metals immobilization from the studied soils was evaluated in experiments in which the plant growth was observed. Heavy metals contaminated soils have been treated with a mixture of organic substance and zeolites (organo - zeolitic material). Zeolitic tuffs were roll-crushed and ground in small grains with dimensions between 0.05 and 2.0 mm. Clinoptilolite is the predominant zeolite and appears as compact masses of tabular and prismatic micron - sized crystals that are evident in SEM images. In the mixture, the polluted soil represents 83% and the organo - zeolitic material represents 17%. The soils used in the experiment are excessive contaminated with Pb (40375-1054ppm) in association with Zn (1175-490ppm), Cd (24.2-13.2ppm) and Cu (409.5-37.6ppm) in Baia Mare zone and with Cu (7000-360ppm) in association with Zn (3100-1900ppm), Cd (80-40ppm) and Pb (2000-50ppm) in Zlatna zone. The original soil and the treated soil have been planted with Lolium perenne. The growth of the plants has demonstrated that the soil treated with organo-zeolitic material allows the growth of vegetation much faster than the original soil. These results show that growth of the plants was possible because the organo-zeolitic material mixed with the soil provides the substances necessary for the plants to develop (ammonium, humus, potassium, calcium). At the same time, heavy metals that inhibit the plant development are blocked through the cationic exchange mechanism that makes them enter the zeolites structure and they no longer directly have access to the plant roots Keywords: soil polluted, organo-zeolitic, plant growth, INTRODUCTION The soils polluted with heavy metals from the affected zones by the mining and metallurgical industry are strongly degraded (eroded), without vegetation and structure. The high level of pollution [...]

The new mineral graţianite, MnBi2S4, is described from the Bǎiţa Bihor skarn deposit, Bihor County, Romania. Graţianite occurs as thin lamellae, intimately intergrown with cosalite and bismuthinite, or as flower-shaped blebs within chalcopyrite, where it is associated with cosalite and tetradymite. Graţianite displays weak to modest bireflectance in air and oil, respectively, and strong anisotropy. The mean empirical composition based on 20 electron probe microanalyses is: (Mn0.541Fe0.319Pb0.070Cu0.040Cd0.009Ag0.001)S0.980(Bi1.975Sb0.018)S1.993(S4.008Se0.012Te0.007)S4.027, corresponding to the ideal formula MnBi2S4. Graţianite crystallizes in the monoclinic system (space group C2/m). Single-crystal X-ray studies of material extracted by the focused ion beam-scanning electron microscopy (FIB-SEM) technique, and carried out on the MX2 macromolecular beamline of the Australian Synchrotron determined the following cell dimensions: a = 12.6774(25) Å, b = 3.9140(8) Å, c = 14.7581(30) Å, b = 115.31(3)°, V = 662.0(2) Å3, and Z = 4. The six strongest X-ray reflections and their relative intensities are: 3.448 Å (100), 2.731 Å (77), 2.855 Å (64), 3.637 Å (55), 3.644 Å (54), and 3.062 Å (51).