Pb isotope data of Pb leach experiment for orthogneiss MU-7 (125 - 250 µm garnet fraction)

Step

Time

Temperature

Acid

²⁰⁶Pb/²⁰⁴Pb

2se

²⁰⁷Pb/²⁰⁴Pb

2se

²⁰⁸Pb/²⁰⁴Pb

2se

1

10 min

Cold

0.5N HBr

19.242

0.009

15.409

0.008

37.744

0.018

2

30 min

120˚C

1N HBr

22.204

0.004

15.542

0.003

38.313

0.006

3

2.5 h

120˚C

4N HBr

53.265

0.037

17.135

0.014

63.852

0.040

4

4 h

120˚C

8.8N HBr

58.390

0.070

17.264

0.045

139.498

0.158

5

18 h

120˚C

8.8N HBr

68.692

0.279

17.859

0.159

153.248

0.552