E1

E2

E3

SiO₂ (wt%)

70.85

70.23

70.74

TiO₂

0.30

0.30

0.30

Al₂O₃

12.72

12.56

12.49

Fe₂O₃*

4.42

4.40

4.19

MnO

0.13

0.14

0.14

MgO

0.08

0.06

0.08

CaO

0.57

0.63

0.74

Na₂O

5.09

4.49

3.98

K₂O

4.99

4.94

4.93

P₂O₅

0.03

0.03

0.02

LOI

0.60

2.00

2.20

Total C

0.08

0.40

0.30

Total

99.77

99.75

99.79

P.I.

1.08

1.01

0.95

D.I.

5.26

4.00

5.52

Be (ppm)

4

<1

2

Rb

56.8

58.6

65.5

Cs

0.2

0.2

0.2

Ba

280

251

240

Sr

23.4

16.4

15.8

V

9

8

<8

Ni

0.9

0.4

0.2

Cr

<20

30

<20

Co

1.4

1.3

0.6

Cu

2.3

0.9

1.1

Cd

0.3

0.4

0.3