Table 5. Helium and argon isotopes in mineral separates from sample SB-3 (gases extracted by melting under 1600oC)

MineralSize, mm4He, 10-6 cc/g3He, 10-9 cc/g4He/3He, 10-6SB-10, mass-fr.
Clinopyroxene >0.315 186.5 0.207 0.901 0.018
Clinopyroxene >0.16 375 0.167 2.24 0.037
Olivine I >0.2 12.6 0.087 0.144 0.001
Olivine I >0.315 8.9 0.141 0.0628 0.0005
Olivine II >0.16 50 0.135 0.369 0.0047
Olivine II >0.2 7.8 0.088 0.0885 0.0005
Olivine II >0.315 38.4 0.246 0.155 0.0031
Olivine II >0.4 54.2 0.165 0.327 0.005
Ti-magnetite >0.16 (3 A) 338 2.74 0.123 0.025
>0.20 (3 A) 340 2.48 0.136 0.027
>0.315(3 A) 250 2.38 0.104 0.017
>0.315(6 A) 426 2.41 0.176 0.036
The whole-rock sample has lost less than 0.5 of the radiogenic in-situ produced He, therefore the present-day concentrations of less movable 3He at least in Ol and Ti-Mgt should be similar to the initial values. In the last column mass-fraction of Perovskite SB-10 is shown; addition of this fraction to the host mineral (col. 1) would explain observed range of 4He concentrations.
A means Ampers: current under which the separation has been performed.

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