Table 2 Chemical composition.

SiO₂

%

21.23

64.02

36.04

94.91

Al₂O₃

5.23

19.89

15.79

1.89

Fe₂O₃

3.51

4.45

0.45

0.36

CaO

60.32

3.82

42.16

0.79

MgO

3.68

1.09

3.94

0.26

SO₃

1.92

–

1.95

–

F-CaO

1.66

–

–

–

K₂O

1.06

1.13

0.50

0.57

Na₂O

0.13

1.04

0.22

0.34

T.A

0.83

–

–

–

LOI

1.26

4.55

0.70

0.88