Grade

Pb ≥ %

Impurity ，≤ %

Cu

Zn

As

MgO

Al 2O3

1 st Grade

2 nd Grade

3 rd Grade

4 th Grade

5 th Grade

6 th Grade

7 th Grade

70

65

60

55

50

45

40

1.5

1.5

1.5

2.0

2.0

2.5

3.0

5

5

5

6

7

8

9

0.3

0.35

0.4

0.5

With discussion

With discussion

With discussion

2

2

2

2

2

2

2

4

4

4

4

4

4

4