ye] i Ty 10000 ASBESTOS MINE COPPEROPOLIS, CALIF. OCTOBER, 1963 = 95 1000— wx 9 E a > » = = [— = = = o a 1.46 MEV. i K 40 ee oo ae 2S 100-- ! | O 20 40 60 80 100 120 140 &O I80 200 CHANNEL NUMBER Figure 3. Field spectrum obtained over freshly exposed serpentine at asbestos mine near Copperopolis, California, This spectrum was accumulated in approximately one hour of live time as opposed to the twenty minute live times for the spectra of Figure 2, —~ 31 -