Sample Constituents, %

Sample No. 1

Sample No. II

Total SiO₂

67.95

66.41

Al₂O₃

16.38

18.13

Fe₂O₃

0.13

0.15

CaO

1.57

2.03

MgO

0.20

0.26

Na₂O

2.09

2.30

K₂O

10.91

10.71

L.O.I.

0.29

0.30

Feldspar Mineral

78.62

87.02