Chemical constituent

Composition (%)

CaO

44.9

K₂O

22.1

Fe₂O₃

11.5

P₂O₅

10.4

TiO₂

1.80

MnO

1.30

ZnO

0.57

Re₂O₇

0.34

SO₃

0.30

CuO

0.27