Variable

Sample Capacity

Minimum Value

Maximum Value

Mean Value

Standard Deviation

Skewness

Kurtosis

SiO₂

69

3.720

96.701

50.180

23.682

0.095

−0.799

Na₂O

69

0.001

8.203

1.079

1.726

1.893

3.901

K₂O

69

0.010

14.749

2.047

3.882

1.946

2.423

CaO

69

0.010

9.935

2.849

2.550

1.093

0.365

MgO

69

0.001

2.912

0.735

0.626

0.664

0.512

Al₂O₃

69

0.450

14.354

4.213

3.157

1.547

2.284

Fe₂O₃

69

0.001

5.938

0.872

1.154

2.028

5.262

CuO

69

0.001

10.584

1.968

2.221

2.181

5.394

PbO

69

0.001

71.185

24.526

20.200

0.311

−1.010

BaO

69

0.000

35.475

7.837

8.506

1.626

2.487

P₂O₅

69

0.010

14.568

2.704

3.636

1.518

1.459

SrO

69

0.001

1.155

0.266

0.268

1.124

0.955

SnO₂

69

0.000

2.365

0.118

0.416

4.586

21.245

SO₂

69

0.001

15.961

0.605

2.659

5.368

28.748