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decays per cm3/s. The spectrum of intrinsic scintillation collected for 114 hours is shown in Fig. 4 . The 1435 keV γ line is seen around channel 1600. We detected about 50 counts per second (cps), including laboratory background, at the gain settings shown in Fig. 4 . A larger counting rate than expected is because of the peaks to the right of the1435 keV γpeak, identified as those due to α-particles originating from a decay of U series isotopes. Characteristic γ- rays from α-decay were detected by Ge detector. The highest α energy and the corresponding peak at about channel 2800 is at 7686 keV from 214Po of the 238U series. Note that Rn gas and the following isotopes of the series are not in age equilibrium in the sample, since it was heated to the melting point recently. We have also checked for possible rare-earth alpha emitters, but the assignment did not fit the spectrum. Based on this assignment of α particles, we estimate α/γ ratio as 0.33±0.01 for the energy of 7.7 MeV, but for lower energy α - particles the number may be lower. The observed α counting rate was 0.89 counts/cm3/s.