Oxyde (%)

TPo

FPo

PjPo

SiO₂

32.61

55

43

TiO₂

5.78

1.8

3.3

Al₂O₃

12.48

15

15

Fe₂O₃

22.65

8.5

14

MgO

6.58

2.9

5.8

CaO

13.58

6.1

11

K₂O

1.01

3.1

1.7

Na₂O

1.16

5.3

4.1

SO₃

0.18

0.9

0.8