Sample

№

Weight

mg

Concentrations, ppm

Isotope composition of Pb

Isotope composition and ages

Rho

Pb

U

²⁰⁶Pb/²⁰⁴Pb

²⁰⁶Pb/²⁰⁷Pb

²⁰⁶Pb/²⁰⁸Pb

²⁰⁷Pb/²³⁵U

²⁰⁶Pb/²³⁸U

²⁰⁷Pb/²⁰⁶Pb

1

0.10

570.5

853.5

377.3

4.4960

4.6981

13.6639

0.520509

2746

0.90

2

0.40

73.4

122.4

1569.7

5.0300

7.3525

13.6052

0.517448

2752

0.96

3

0.20

105.6

62.5

39.4

2.0155

0.9683

13.1366

0.502440

2739

0.59

4

0.20

30.9

55.2

898.6

4.9505

6.5013

12.2840

0.472568

2729

0.95

5

0.20

139.6

170.5

1115.2

3.8733

3.3616

20.6889

0.604176

3174

0.97