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We studied the transport properties of American chalcopyrite ore in a wide range of temperatures. Electrical resistivity of the sample is studied both at low (77–300 K) and high temperature (300–450 K), thermoelectric power from 300 K to 400 K, and AC magnetic susceptibility in the temperature range 77–300 K. The electrical resistivity measurement shows step wise increasing conductivity with increasing temperature that is quantum conductance is observed. Thermoelectric power measurement in the temperature range 300–400 K shows a wriggling effect. Susceptibility measurement in the temperature range 77–300 K shows a positive peak at 80 K, hence a ferromagnetic response and a negative peak at 90 K shows a diamagnetic response. Later on, when increasing the temperature up to 300 K, the susceptibility is positive and almost remains constant, which reveals an antiferromagnetic behavior in the temperature range 150–300 K. The characterization of the sample (American chalcopyrite) is done by using scanning electron microscopy (SEM), energy dispersive x-ray spectroscopy (EDS) and x-ray diffraction (XRD) analysis. The SEM analysis shows the surface of the chalcopyrite sample with two different phases. The EDS analysis reveals that the sample contains copper (Cu) 19%, iron (Fe) 23% and sulfur (S) 20% by atomic percent, along with some other impurities. On the basis of this composition we suggest that chalcopyrite is a semiconductor as it contains oxygen (O), carbon (C) and sulfur (S) as impurity elements. The XRD analysis shows that the sample has a body-centered tetragonal structure.

Electrical resistivity measurements in Iron-Zirconium liquid quinched amorphous alloys, in the temperature range 273 K ≤ T ≤ 900 K, show temperature dependent nucleus size. For Fe 20 Zr 80 , Fe 24 Zr 76 and Fe 35 Zr 65 LQA alloys the nucleus is ascribed to triple, double and single stage metal-insulator transitions respectively. These temperature dependent transitions define a curved Arrhenius plot.